ROLL COATING-BASED PREPARATION METHODS FOR ADHESIVE BONDING OF ALUMINUM ALLOYS, AND PRODUCTS RELATING TO THE SAME

Abstract

Methods for preparing an aluminum alloy sheet product for adhesive bonding are disclosed. A method may include preparing an aluminum alloy product for roll coating and roll coating an aqueous functionalization solution onto the prepared aluminum alloy product. For the roll coating step, the aqueous functionalization solution may include from 0.1 to 5.0 wt. % of active ingredients. The active ingredients may include a first monomer component and a second polymer component. The amount of second polymer component in the aqueous functionalization solution may be greater than an amount of the first monomer component in the aqueous functionalization solution.

Claims

1. A method comprising: (a) preparing an aluminum alloy product for roll coating; (b) rinsing the prepared aluminum alloy product; (c) roll coating an aqueous functionalization solution onto the prepared aluminum alloy product; (i) wherein the aqueous functionalization solution comprises from 0.1 to 5.0 wt. % of active ingredients; (ii) wherein the active ingredients comprise a first monomer component and a second polymer component; and (iii) wherein an amount of the second polymer component in the aqueous functionalization solution is greater than an amount of the first monomer component in the aqueous functionalization solution; and (d) drying the roll coated aluminum alloy product.

2. The method of claim 1, wherein the preparing step (a) comprises deoxidizing the aluminum alloy product with an acid.

3. The method of claim 2, wherein the preparing step (a) comprises maintaining the acid at a temperature of from room temperature to 185 F.

4. The method of claim 2, wherein the preparing step (a) comprises maintaining the acid at a temperature of from 130 to 185 F.

5. The method of claim 2, wherein the preparing step (a) comprises maintaining the acid at a temperature of at least 165 F.

6. The method of claim 1, wherein the roll coating step (c) comprises maintaining the aqueous functionalization solution at a temperature of from room temperature to 110 F.

7. The method of claim 1, wherein the roll coating step (c) comprises maintaining a ratio of the amount of the first monomer component to the amount of the second polymer component from 1:19 to 7:13.

8. The method of claim 1, wherein: the aluminum alloy product comprises an aluminum alloy sheet having an upper surface and a lower surface; and the roll coating step (c) comprises roll coating the aqueous functionalization solution onto at least one of the upper surface and the lower surface.

9. The method of claim 8, wherein the roll coating step (c) comprises roll coating the aqueous functionalization solution onto both the upper surface and the lower surface.

10. The method of claim 9, wherein the roll coating step (c) comprises: maintaining a first volume of the aqueous functionalization solution at a first concentration of the active ingredients for roll coating onto the upper surface; and maintaining a second volume of the aqueous functionalization solution at a second concentration of the active ingredients for roll coating onto the lower surface.

11. The method of claim 10, wherein the second concentration is equal to the first concentration.

12. The method of claim 10, wherein the second concentration is different from the first concentration.

13. The method of claim 12, wherein the second concentration is greater than the first concentration.

14. The method of claim 13, wherein the first concentration is at least 0.25 wt. % less than the second concentration.

15. The method of claim 13, wherein the first concentration is at least 0.50 wt. % less than the second concentration.

16. The method of claim 13, wherein the first concentration is at least 0.6 wt. % less than the second concentration.

17. The method of claim 13, wherein the second concentration is not greater than 1.75 wt. %.

18. The method of any of the preceding claims, wherein the aqueous functionalization solution comprises 0.2-2.5 wt. % of active ingredients.

19. The method of claim 1, wherein the drying step (d) is performed in the absence of rinsing after the roll coating step (c).

20. The method of claim 1, comprising maintaining the aluminum alloy product at a peak metal temperature of from 150 to 300 F.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0059] FIG. 1 is a block diagram of a roll coating-based process for preparing an aluminum alloy sheet product for adhesive bonding.

[0060] FIGS. 2A-2C are block diagrams illustrating alternative embodiments of roll coating apparatus.

[0061] FIG. 3 is a flow chart illustrating one embodiment of a method for producing prepared aluminum alloy products in accordance with the present disclosure.

[0062] FIG. 4 is a flow chart illustrating one embodiment of the preparing step of FIG. 3.

[0063] FIG. 5 is a flow chart illustrating one embodiment of the roll coating step of FIG. 3.

[0064] FIG. 6 is a flow chart illustrating an additional embodiment of the roll coating step of FIG. 3.

[0065] FIG. 7 is a flow chart illustrating one embodiment of the drying step of FIG. 3.

DETAILED DESCRIPTION

Example 1

[0066] Several aluminum alloy sheet products were produced from both 6xxx (e.g., 6111) and 5xxx (e.g., 5754) alloys. The 6111 aluminum alloy sheets were processed to a T4 temper and the 5754 aluminum alloy sheets were processed to an O temper. For each of the 6111-T4 and 5754-O sheets, 8 sheet specimens were subject to a batch process. The sheet specimens were alkaline cleaned by spraying with an alkaline solution (4 wt. % of an alkaline carbonate cleaner) to remove residual lubricants and general contamination. The alkaline solution was maintained at 140 F. and the sheet specimens were allowed to contact the alkaline solution for 4 seconds. After the alkaline cleaning, the sheet specimens were rinsed with deionized water after the alkaline cleaning was performed.

[0067] After the alkaline cleaning step, the sheet specimens were deoxidized by spraying them with an acidic solution (nitric acid at 4 wt. %). The acidic solution was maintained at 120 F. and the sheet specimens were allowed to contact the acidic solution for 4 seconds. After the acid deoxidization step, the sheet specimens were rinsed with deionized water. Also, all sheet specimens were verified after the post-acid deoxidization rinse for water break-free behavior by visual inspection.

[0068] Next, two sets of 4 specimens for each of the 6111-T4 and 5754-O sheets were contacted with an aqueous functionalization solution in the form of a phosphorus-containing organic acid (PCOA) solution maintained at 90 F. The PCOA included a solution mixture of active ingredients including a first monomer component (component A) and a second polymer component (B). For Example 1, component A was a polymer, as per U.S. Pat. No. 6,167,609, and component B was a copolymer, as per U.S. Pat. No. 6,020,030. The amount of component A exceeded the amount of component B in the solution. For the first set, the sheet specimens were immersed in the PCOA for 10 seconds, followed by rinsing with deionized water and air drying. For the second set, the PCOA was applied to the sheet specimens using a drawdown bar to simulate roll coating application. Rather than rinsing the second set sheet specimens as for the first set, the second set specimens proceeded directly to a heated drying step after the PCOA was applied. The drying of the second set sheet specimens was performed at a peak metal temperature of 350 F. For both the first and second sets, the sheet specimens were then sequentially bonded and then subjected to bond durability testing (BDT) according to an automotive industry standard cyclical corrosion exposure test. This bond durability testing included a combination of applied lap sheer stress and environmental exposure (the BDT test). The BDT results of the specimens of the Example 1 aluminum alloy sheets are provided in Table 1, below.

TABLE-US-00001 TABLE 1 BDT Test Results Number of BDT Cycles Survived PCOA 6111-T4 5754-O Application Specimen No. Specimen No. Method 1 2 3 4 1 2 3 4 Immersion 45 45 45 45 45 45 45 45 Drawdown Bar 0 0 0 0 1 1 1 1

[0069] In Table 1, above, a specimen having survived 45 BDT cycles represents a passing BDT test result. For both the 6111-T4 and 5754-O sheets of Example 1, all specimens achieved passing BDT test results. With the PCOA having A:B=3:1 applied using the drawdown bar, however, no specimens of the 5754-O sheets survived greater than 1 BDT cycle, while for the 6111-T4 sheets, all specimens failed after initial stress was applied to the rings and prior to commencing the environment exposure portion of the BDT test.

Example 2

[0070] Based on the Example 1 results, several aluminum alloy sheet products were produced from both 6xxx (e.g., 6022, 6111) and 5xxx (e.g., 5754) alloys. All 6xxx aluminum alloys were processed to a T4 temper and all 5xxx aluminum alloys were processed to an O temper. Using a batch process, sheet specimens were alkaline cleaned with an alkaline solution (a buffered alkaline solution) to remove residual lubricants and general contamination. The sheet specimens were immersed for 2 minutes in the alkaline solution maintained at 140 F. The sheet specimens were then rinsed with deionized water after the alkaline cleaning was performed.

[0071] The sheet specimens were then deoxidized with an acidic solution (BONDERITE C-IC 243 at 14% by volume). The sheet specimens were immersed for 20 seconds in the acidic solution maintained at 170 F. All specimens were rinsed with deionized water after the acid deoxidization was performed. Also, all sheet specimens were verified after the post-acid deoxidization rinse for water break-free behavior by visual inspection.

[0072] Following the verification of water break-free behavior, an aqueous functionalization solution in the form of a phosphorus-containing organic acid (PCOA) was applied by pipetting onto the surfaces of the aluminum alloy sheet specimens. Next, roll coating was performed by passing the specimens, with the PCOA applied to them, through squeegee rolls to meter the PCOA over the surfaces of the specimens. The PCOA included a solution mixture of active ingredients including a first monomer component (component A) and a second polymer component (B). Component A and B were the same compounds as per Example 1. Various roll coat conditions were used, as shown in Tables 2A-2C, below.

[0073] Instead of rinsing the aluminum alloy sheet specimens after the roll coating step, the sheet specimens proceeded directly to drying, where the specimens were subjected to various heated forced air drying conditions with the peak metal temperatures (PMT) being maintained at from 150 to 270 F., as shown in Tables 2A-2C, below. Initial X-ray fluorescence (XRF) analysis for phosphorus coating weight was performed following completion of drying. After the initial XRF analysis, a hot deionized water rinse was completed followed by re-measurement of phosphorus coating weight by XRF to assess adhesion of the treatment. The sheet specimens were then sequentially bonded and then subjected to bond durability testing (BDT) according to an automotive industry standard cyclical corrosion exposure test.

[0074] The results of the XRF testing of specimens of 6022-T4(1), 6111-T4, 6022-T4(2), and 5754-O aluminum alloy sheets from Example 2 are provided in Tables 2A-2C, below. As used herein, T4(1) refers to a first 6022 sheet in the T4 temper and T4(2) refers to a second 6022 sheet in the T4 temper. In Tables 2A-2C, below, each XRF test result represents the average of four replicate test results of four specimens per sheet. Also, in Tables 2A-2C, below, sheets having a post-drying coat weight of from 0.21 to 3.55 mg/m.sup.2 P are deemed passing (P) results. If an initial XRF result for post-drying phosphorus coating weight was not within the 0.21-3.55 mg/m.sup.2 P range, that sheet was deemed a failing (F) result. Results from re-measurement of phosphorus coating weight by XRF after the post-drying hot deionized water rinse are classified into three categories in Tables 2A-2C: (1) a reduction in phosphorus coating weight of less than 10%; (2) a reduction in phosphorus coating weight of 10-15%; and (3) a greater than 15% reduction in phosphorus coating weight. The BDT results of the specimens of the Example 2 aluminum alloy sheets are provided in Tables 3A-3C, below.

TABLE-US-00002 TABLE 2A XRF Test Results for 150 F. PMT 6022-T4(1) 6111-T4 6022-T4(2) 5754-O Post-Hot Post-Hot Post-Hot Post-Hot Concen- Concen- Initial Water Initial Water Initial Water Initial Water tration tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF (A + B, Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss wt. %) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 1 5:95 P >15 P <10 P 10-15 P <10 1 35:65 P >15 P >15 F >15 P 10-15 2.5 5:95 P 10-15 P >15 P 10-15 P >15 2.5 35:65 F >15 P >15 P <10 P >15

TABLE-US-00003 TABLE 2B XRF Test Results for 180 F. PMT 6022-T4(1) 6111-T4 6022-T4(2) 5754-O Post-Hot Post-Hot Post-Hot Post-Hot Concen- Concen- Initial Water Initial Water Initial Water Initial Water tration tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF (A + B, Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss wt. %) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 1 5:95 P >15 P <10 P 10-15 P 10-15 1 35:65 P >15 P >15 P >15 F >15 2.5 5:95 P 10-15 P >15 P >15 P >15 2.5 35:65 F >15 P >15 P >15 P >15

TABLE-US-00004 TABLE 2C XRF Test Results for 210 F. PMT 6022-T4(1) 6111-T4 6022-T4(2) 5754-O Post-Hot Post-Hot Post-Hot Post-Hot Concen- Concen- Initial Water Initial Water Initial Water Initial Water tration tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF (A + B, Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss wt. %) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 1 5:95 P >15 P 10-15 P <10 P >15 1 35:65 P >15 P >15 P 10-15 P >15 2.5 5:95 P >15 P 10-15 P 10-15 P <10 2.5 35:65 P >15 F >15 P >15 P >15

TABLE-US-00005 TABLE 3A BDT Test Results for 150 F. PMT Concentration Concentration Number of Specimens Failing Prior to Completing 45 BDT Cycles (A + B, wt. %) Ratio (A:B) 6022-T4(1) 6111-T4 6022-T4(2) 5754-O 1 5:95 2 (28) 0 1 (34) 0 1 35:65 1 (34) 0 1 (34) 1 (37) 2.5 5:95 1 (34) 0 0 0 2.5 35:65 2 (2) 2 (39) 0 0

TABLE-US-00006 TABLE 3B BDT Test Results for 180 F. PMT Concentration Concentration Number of Specimens Failing Prior to Completing 45 BDT Cycles (A + B, wt. %) Ratio (A:B) 6022-T4(1) 6111-T4 6022-T4(2) 5754-O 1 5:95 1 (34) 2 (27) 0 0 1 35:65 0 0 0 0 2.5 5:95 0 0 0 0 2.5 35:65 2 (23) 2 (12) 0 0

TABLE-US-00007 TABLE 3C BDT Test Results for 210 F. PMT Concentration Concentration Number of Specimens Failing Prior to Completing 45 BDT Cycles (A + B, wt. %) Ratio (A:B) 6022-T4(1) 6111-T4 6022-T4(2) 5754-O 1 5:95 0 1 (34) 0 1 (34) 1 35:65 0 2 (2) 0 0 2.5 5:95 0 1 (38) 0 0 2.5 35:65 0 2 (11) 0 0

[0075] In Tables 3A-3C, above, each BDT result represents the average of four replicate specimens per sheet. Also, in Tables 3A-3C, above, BDT results are classified into three categories: (1) all specimens achieving at least 45 cycles of BDT (e.g., no failing specimens); (2) one specimen not achieving 45 BDT cycles; and (3) 2 or more specimens not achieving 45 BDT cycles. In Tables 3A-3C, in cases where one or more tested specimens did not successfully attain 45 BDT cycles, the average number of cycles that the four tested specimens attained is shown in parentheses.

[0076] In Example 2, for the 6022-T4(1) and 6022-T4(2) sheets, all BDT tests achieved 45 cycles across all the (A+B) concentration and A:B ratios for the 210 F. PMT condition. Also, for the 6022-T4(1) sheets at the 210 F. PMT, and for all the (A+B) concentration and A:B ratios, all post-drying rinse XPF results show greater than 15% phosphorus loss. A similar effect was observed for the 6022-T4(2) sheets at the 180 F. PMT. Also, at the 180 F. PMT condition, all 6022-T4(1) sheet specimens achieved 45 BDT cycles for the (A+B) concentrations of 1 and 2.5, and the A:B ratio of 35:65. The worst BDT test performance was observed for the 6022-T4(1) sheets at the 150 F. PMT condition, for which there were no results achieving 45 BDT cycles. For 6022-T4(1), there were no results for any of the tested conditions where 45 BDT were achieved in combination with less than 10% loss of phosphorus after the post-drying rinse. For 6022-T4(2), on the other hand, 45 BDT cycles were achieved concomitantly with less than 10% post-drying rinse phosphorus coating weight reduction in two cases: (1) PMT=150 F., (A+B) concentration=2.5 wt. %, and A:B=35:65; and (2) PMT=210 F., (A+B) concentration=1 wt. %, and A:B=5:95. It thus appears that for 6022 aluminum alloy sheets, BDT performance depends more on PMT than it does on (A+B) concentration and/or A:B for the PCOA applied by roll coating, with higher PMTs promoting better bond durability.

[0077] For the 6111 sheets in Example 2, only one test result was obtained where 45 BDT cycles were achieved along with less than 10% loss of phosphorus after the post-drying rinse: PMT=150 F., (A+B) concentration=1 wt. %, and A:B=5:95. The 150 F. PMT condition also yielded the best overall BDT performance, where 45 BDT cycles were attained for all but the condition with (A+B) concentration=2.5 and A:B=35:65. At the 180 F. PMT condition, 45 BDT cycles were obtained for only 2 of 4 tests. The worst bonding performance was observed for the 210 F. PMT condition, where none of the tests attained 45 BDT cycles. Thus, in contrast to the trend observed for 6022, for 6111 aluminum alloy sheets, it appears that lower PMTs promote better bond durability.

[0078] For the 5754 sheets in Example 2, bonding performance appears to depend neither upon PMT, nor (A+B) concentration and/or A:B ratio conditions. For 5754, 45 BDT cycles were attained for all but two sets of conditions: (1) PMT=150 F., (A+B) concentration=1, and A:B=35:65 (result included 10-15% post-drying rinse loss in phosphorus coating weight); and (2) PMT=210 F., (A+B) concentration=1, and A:B=5:95 (result included greater than 15% post-drying loss in phosphorus coating weight). Similarly, little to no correlation was observed between post-drying rinse phosphorus coating weight loss and PMT, (A+B) concentration and/or A:B ratio.

[0079] Overall, the results obtained in Example 2 demonstrate that PMT, (A+B) concentration, and A:B ratio, and combinations thereof, appear to be important parameters for achieving desired bonding performance of the tested alloys after roll coating-based application of the PCOA. The observed effects appear to be dependent on the composition of the aluminum alloy sheet and, therefore, the conditions described above may be adjusted to achieve the desired bond durability after using roll coating-based preparation methods. This tailoring of conditions may include varying PMT, (A+B) concentration, and A:B ratio, and combinations thereof, between the upper and lower surfaces of the aluminum alloy sheet products.

Example 3

[0080] Based on the Example 2 results, several aluminum alloy sheet products were produced from both 6xxx (e.g., 6022) and 5xxx (e.g., 5754) alloys. All 6xxx aluminum alloys were processed to a T4 temper and all 5xxx aluminum alloys were processed to an O temper. Using a continuous, coil-to-coil process, the sheets were uncoiled and then alkaline cleaned with an alkaline solution (potassium hydroxide-based) to remove residual lubricants and general contamination. The upper and lower surfaces of the sheets were sprayed with the alkaline solution maintained at 140 F. and for a contact time of 4 seconds. The upper and lower sheet surfaces were then rinsed with deionized water after the alkaline cleaning was performed.

[0081] Upper and lower surfaces of the sheets were then deoxidized by spraying with an acidic solution and for a contact time of 4 seconds. Three different deoxidization conditions were used: (1) 4% by weight nitric acid maintained at 140 F.; (2) 14% by volume BONDERITE C-IC 243 maintained at 170 F.; and (3) 4% by volume GARDOCLEAN S5149 (formerly known as DC 7853) maintained at 130 F. and containing H7274 additive to provide 200 ppm free fluoride. The upper and lower sheet surfaces were rinsed with deionized water after the acid deoxidization was performed. Also, all sheets were verified after the post-acid deoxidization rinse for water break-free behavior by visual inspection.

[0082] Following the verification of water break-free behavior, an aqueous functionalization solution (the PCOA as described above for Example 2) was applied to both the upper and lower surfaces of the sheets by roll coating. For the roll coating step, the PCOA was applied with squeegee rolls using coating against tension for both the upper and lower sheet surfaces. Also, for Example 3 the aluminum alloy sheets were fed through the continuous coil-to-coil process at 122 feet per minute. The (A+B) concentration for the upper surface PCOA roll coating was maintained at 0.625 wt. % and the (A+B) concentration for the lower surface PCOA roll coating was maintained at 1.25 wt. %. In Example 3, a ratio of the concentration of A to the concentration of B (A:B) in the applied PCOA was set at either 5:95 and 35:65.

[0083] Instead of rinsing the aluminum alloy sheets after the roll coating step, the sheets proceeded directly to drying, where they were subjected to various heated forced air drying conditions with the PMTs being maintained at from 150 to 210 F., as shown in Tables 4A-4C, below. XRF analysis and BDT tests were performed as described above in reference to Example 2.

[0084] The results of the XRF testing of specimens of 6022-T4(1) and 5754-O aluminum alloy sheets from Example 3 are provided in Tables 4A-4C, below. In Tables 4A-4C, below, each XRF test result represents the average of four replicate test results of four specimens per sheet. Also, in Tables 4A-4C, below, sheets having a post-drying coat weight of from 0.21 to 3.55 mg/m.sup.2 P are deemed passing (P) results. If an initial XRF result for post-drying phosphorus coating weight was not within the 0.21-3.55 mg/m.sup.2 P range, that sheet was deemed a failing (F) result. Results from re-measurement of phosphorus coating weight by XRF after the post-drying hot deionized water rinse are classified into three categories in Tables 4A-4C: (1) a reduction in phosphorus coating weight of less than 10%; (2) a reduction in phosphorus coating weight of 10-15%; and (3) a greater than 15% reduction in phosphorus coating weight. The BDT results of the 6022-T4(1) and 5754-O aluminum alloy sheets from Example 3 are provided in Tables 5A-5C, below.

TABLE-US-00008 TABLE 4A XRF Test Results for BONDERITE C-IC 243 Deox Upper Sheet Surface Lower Sheet Surface 0.625 wt. % (A+B) 1.25 wt. % (A+B) 5754-O 6022-T4(1) 5754-O 6022-T4(1) Post-Hot Post-Hot Post-Hot Post-Hot Concen- Initial Water Initial Water Initial Water Initial Water tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 150 5:95 P <10 P >15 P <10 P <10 35:65 P <10 P >15 P <10 P <10 180 5:95 P <10 P >15 P <10 P <10 35:65 P <10 P >15 P <10 P <10 210 5:95 P <10 P >15 P <10 P <10 35:65 P <10 P >15 P <10 P <10

TABLE-US-00009 TABLE4B XRF Test Results for Nitric Acid Deox Upper Sheet Surface Lower Sheet Surface 0.625 wt. % (A + B) 1.25 wt. % (A + B) 5754-O 6022-T4(1) 5754-O 6022-T4(1) Post-Hot Post-Hot Post-Hot Post-Hot Concen- Initial Water Initial Water Initial Water Initial Water tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 150 5:95 P >15 P >15 P <10 P >15 35:65 P <10 P >15 P >15 P >15 180 5:95 P >15 P >15 P >15 P >15 35:65 P <10 P >15 P >15 P >15 210 5:95 P >15 P >15 P <10 P >15 35:65 P <10 F <10 P >15 F <10

TABLE-US-00010 TABLE 4C XRF Test Results for GARDOCLEAN S5149 Deox Upper Sheet Surface Lower Sheet Surface 0.625 wt. % (A + B) 1.25 wt. % (A + B) 5754-O 6022-T4(1) 5754-O 6022-T4(1) Post-Hot Post-Hot Post-Hot Post-Hot Concen- Initial Water Initial Water Initial Water Initial Water tration XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Ratio (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) (A:B) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 150 5:95 P >15 P >15 P >15 P >15 35:65 P >15 P <10 P >15 P <10 180 5:95 P <10 P >15 P >15 P <10 35:65 P >15 P <10 P >15 P <10 210 5:95 P <10 P >15 P >15 P <10 35:65 P >15 P <10 P >15 P <10

TABLE-US-00011 TABLE 5A BDT Test Results for BONDERITE C-IC 243 Deox Number of Specimens Failing Concentration Prior to Completing 45 BDT Cycles PMT ( F.) Ratio (A:B) 5754-O 6022-T4(1) 150 5:95 1 (31) 0 35:65 0 0 180 5:95 0 1 (36) 35:65 0 1 (37) 210 5:95 0 0 35:65 0 0

TABLE-US-00012 TABLE 5B BDT Test Results XRF for Nitric Acid Deox Number of Specimens Failing Concentration Prior to Completing 45 BDT Cycles PMT ( F.) Ratio (A:B) 5754-O 6022-T4(1) 150 5:95 0 0 35:65 0 0 180 5:95 0 1 (31) 35:65 0 0 210 5:95 0 0 35:65 0 1 (40)

TABLE-US-00013 TABLE 5C BDT Test Results for GARDOCLEAN S5149 Deox Number of Specimens Failing Prior Concentration to Completing 45 BDT Cycles PMT ( F.) Ratio (A:B) 5754-O 6022-T4(1) 150 5:95 0 0 35:65 0 0 180 5:95 0 0 35:65 0 0 210 5:95 0 0 35:65 0 0

[0085] In Tables 5A-5C, above, each BDT result represents the average of four replicate specimens per sheet. Also, in Tables 5A-5C, above, BDT results are classified into three categories: (1) all specimens achieving at least 45 cycles of BDT (e.g., no failing specimens); (2) one specimen not achieving 45 BDT cycles; and (3) 2 or more specimens not achieving 45 BDT cycles. None of the BDT test results of Example 3 included more than 1 specimen failing prior to achieving 45 cycles. In Tables 5A-5C, in cases where one tested specimen did not successfully attain 45 BDT cycles, the average number of cycles that the four tested specimens attained is shown in parentheses.

[0086] In Example 3, for the 6022-T4(1) sheets deoxidized with GARDOCLEAN S5149, despite observed variations in post-drying rinse phosphorus coating weight losses between upper and lower sheet surfaces, all BDT tests achieved 45 cycles across all the (A+B) concentrations and A:B ratios for all PMT conditions. Also, for the 6022-T4(1) sheets at all PMT conditions, use of BONDERITE C-IC 243 deoxidizer yielded the best results for post-drying rinse phosphorus retention on the lower surface, with all results showing less than 10% loss. Lower surface phosphorus retention results were only nominally worse for GARDOCLEAN S5149 as compared to BONDERITE C-IC 243. Use of BONDERITE C-IC 243, however, yielded the worst phosphorus retention for the upper surface, with nitric acid providing only marginally better results for this measure. For the 6022-T4(1) sheets of Example 3, overall BDT results were comparable between BONDERITE C-IC 243 and nitric acid, despite the observation that nitric acid resulted in the worst lower surface phosphorus retention. With the tested BONDERITE C-IC 243 and nitric acid deoxidizer formulations, overall BDT performance was only nominally worse as compared to 6022-T4(1) sheets deoxidized using GARDOCLEAN S5149. A greater than 15% loss of phosphorus from the upper surface was observed after the post-drying rinse for deoxidization using BONDERITE C-IC 243 for all tested conditions, while in all cases, less than 10% phosphorus was lost from the lower surface deoxidized with BONDERITE C-IC 243. Using nitric acid for deoxidization of the 6022-T4(1) sheets led to greater than 15% loss of phosphorus from both the upper and lower surfaces in all but one case: PMT=210 F., (A+B) concentrations=0.625 and 1.25 wt. % for the lower and upper surfaces, respectively, and A:B=35:65 (less than 10% reduction in phosphorus observed for this case). It thus appears that for 6022 aluminum alloy sheets, BDT performance may be more dependent on the formulation used for the deoxidization step than it is on the A:B ration of the PCOA applied by roll coating, but the A:B condition may be correlated with variations in observed phosphorus coating weight retention between the lower and upper surfaces.

[0087] Also, in Example 3, use of GARDOCLEAN S5149 and nitric acid for deoxidizing the 5754 sheets yielded the best BDT results overall, with all tests attaining 45 cycles across all conditions, despite observed variations in upper and lower surface phosphorus losses. BONDERITE C-IC 243, on the other hand, provided the best post-drying rinse phosphorus retention results for the 5754 sheets. Deoxidization of the 5754 sheets using GARDOCLEAN S5149 yielded the worst results for phosphorus retention for both the upper and lower surfaces, but only nominally so for the upper surface as compared to use of nitric acid. Therefore, it appears that for 5754 aluminum alloy sheets, overall bonding performance is not greatly correlated with either PMT or the formulation used for the acid deoxidization step. However, there does appear to be some dependency between post-drying step phosphorus retention results and deoxidizer formulation used. It appears that PMT and/or A:B ratio may be correlated with observed differences in phosphorus retention on the lower surface as compared to the upper surface for 5754 sheets.

[0088] Overall, the results obtained in Example 3 demonstrate that PMT and A:B ratio, and combinations thereof, appear to be important parameters for achieving desired bonding performance of the tested alloys after roll coating-based application of the PCOA. The observed effects appear to be dependent on the composition of the aluminum alloy sheet and, therefore, the conditions described above may be adjusted to achieve the desired bond durability after using roll coating-based preparation methods. This tailoring of conditions may include varying deoxidizer formulation, PMT, and A:B ratio, and combinations thereof, between the upper and lower surfaces of the aluminum alloy sheet products.

Example 4

[0089] Aluminum alloy sheets were subjected to the procedure and conditions of Example 3, except that in Example 4, a PMT of 240 F. replaced the 150 F. PMT, and an A:B condition of 10:90 replaced the 5:95 A:B. Also, in Example 4, BONDERITE C-IC 243 and GARDOCLEAN S5149, but not nitric acid, were used for the acid deoxidization step. For Example 4, the aluminum alloy sheets, the (A+B) concentration of the PCOA was either maintained at the same concentration for the upper and lower surfaces, or the (A+B) concentration was less for the upper surface as compared to the lower surface (see Table 6B, below). XRF analysis and BDT tests were performed as described above in reference to Example 2.

[0090] The results of the XRF testing of 6022-T4(1) and 5754-O aluminum alloy sheets from Example 4 are provided in Tables 6A and 6B, below. In Tables 6A and 6B, below, each XRF test result represents the average of four replicate test results of four specimens per sheet. Also, in Tables 6A and 6B, below, sheets having a post-drying coat weight of from 0.21 to 3.55 mg/m.sup.2 P are deemed passing (P) results. If an initial XRF result for post-drying phosphorus coating weight was not within 0.21-3.55 mg/m.sup.2 P, that sheet was deemed a failing (F) result (no failing initial XRF results observed for Example 4). Results from re-measurement of phosphorus coating weight by XRF after the post-drying hot deionized water rinse are classified into three categories in Tables 6A and 6B: (1) a reduction in phosphorus coating weight of less than 10%; (2) a reduction in phosphorus coating weight of 10-15%; and (3) a greater than 15% reduction in phosphorus coating weight. Also, in Tables 6A and 6B, below, a sheet for which XRF testing was not performed is indicated by double dashes (--). The BDT results of the 6022-T4(1) and 5754-O aluminum alloy sheets from Example 4 are provided in Tables 7A and 7B, below.

TABLE-US-00014 TABLE 6A XRF Test Results for BONDERITE C-IC 243 Deox Upper Sheet Surface Lower Sheet Surface Concentration Concentration 5754-O 6022-T4(1) 5754-O 6022-T4(1) (A + B, wt. %) Ratio (A:B) Post-Hot Post-Hot Post-Hot Post-Hot (For Both Upper (For Both Upper Initial Water Initial Water Initial Water Initial Water & Lower Surfaces, & Lower Surfaces, XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Unless Otherwise Unless Otherwise (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) Specified) Specified) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 180 0.625 10:90 P <10 P >15 P <10 P <10 0.625 35:65 P >15 P >15 P >15 P >15 210 0.625 10:90 P <10 P >15 P <10 P <10 0.625 35:65 P >15 P >15 P >15 P >15 240 0.625 10:90 P <10 P >15 P <10 P <10 0.625 35:65 P >15 P >15 P >15 P >15

TABLE-US-00015 TABLE 6B XRF Test Results for GARDOCLEAN S5149 Deox Upper Sheet Surface Lower Sheet Surface Concentration Concentration 5754-O 6022-T4(1) 5754-O 6022-T4(1) (A + B, wt. %) Ratio (A:B) Post-Hot Post-Hot Post-Hot Post-Hot (For Both Upper (For Both Upper Initial Water Initial Water Initial Water Initial Water & Lower Surfaces, & Lower Surfaces, XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Unless Otherwise Unless Otherwise (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) Specified) Specified) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 180 0.625 10:90 P >15 P >15 P <10 P <10 0.625 35:65 P >15 P <10 P >15 P <10 210 0.625 10:90 P >15 P >15 P <10 P <10 0.625 35:65 P >15 P >15 P >15 P <10 0.625 10:90 P <10 P <10 (upper) 1.25 (lower) 240 0.625 10:90 P >15 P <10 0.625 35:65 P >15 P >15 P >15 P <10 0.625 10:90 P <10 P <10 (upper) 1.25 (lower) 1.25 10:90 >15 <10 1.25 35:65 P >15 P <10 (upper) 10:90 (lower)

TABLE-US-00016 TABLE 7A BDT Test Results for BONDERITE C-IC 243 Deox Concentration (A + B, wt. %) Concentration Ratio (A:B) (For Both Upper & Lower (For Both Upper & Lower Number of Specimens Failing Prior Surfaces, Unless Otherwise Surfaces, Unless Otherwise to Completing 45 BDT Cycles PMT ( F.) Specified) Specified) 5754-O 6022-T4(1) 180 0.625 10:90 0 0 0.625 35:65 0 0 210 0.625 10:90 0 0 0.625 35:65 0 0 240 0.625 10:90 0 1 (41) 0.625 35:65 0 0

TABLE-US-00017 TABLE 7B BDT Test Results for GARDOCLEAN S5149 Deox Concentration (A + B, wt. %) Concentration Ratio (A:B) (For Both Upper & Lower (For Both Upper & Lower Number of Specimens Failing Prior Surfaces, Unless Otherwise Surfaces, Unless Otherwise to Completing 45 BDT Cycles PMT ( F.) Specified) Specified) 5754-O 6022-T4(1) 180 0.625 10:90 1 (39) 0 0.625 35:65 0 0 210 0.625 10:90 0 0 0.625 35:65 0 0 0.625 (upper) 10:90 0 1.25 (lower) 240 0.625 10:90 0 0.625 35:65 0 0 0.625 (upper) 10:90 0 1.25 (lower) 1.25 10:90 0 1.25 35:65 (upper) 0 10:90 (lower)

[0091] In Tables 7A and 7B, above, each BDT result represents the average of four replicate specimens per sheet. Also, in Tables 7A and 7B, above, BDT results are classified into three categories: (1) all specimens achieving at least 45 cycles of BDT (e.g., no failing specimens); (2) one specimen not achieving 45 BDT cycles; and (3) 2 or more specimens not achieving 45 BDT cycles. None of the BDT test results of Example 4 included more than 1 bonding failure prior to achieving 45 cycles. In Tables 7A and 7B, in cases where one specimen did not successfully attain 45 BDT cycles, the average number of cycles that the four specimens attained is shown in parentheses. A sheet for which BDT testing was not performed is indicated by double dashes (--) in Tables 7A and 7B, above.

[0092] In Example 4, for the 6022-T4(1) sheets deoxidized with BONDERITE C-IC 243, all but one of the BDT test conditions (PMT=240 F., (A+B) concentrations=0.625 for both the lower and upper surfaces, and A:B=10:90) achieved 45 cycles. In that case, the specimens achieved an average of 41 BDT cycles. Also, for the 6022-T4(1) sheets deoxidized with BONDERITE C-IC 243, the 3 specimens for the A:B=35:65 condition showed greater than 15% post-hot water rinse loss of phosphorus from their lower surfaces, and all the specimens lost greater than 15% of the phosphorus coating weight after that step for their upper surfaces. Also, in Example 4, for the 6022-T4(1) sheets deoxidized with GARDOCLEAN S5149, all BDT test conditions provided 45 cycles. All the specimens for the 6022-T4(1) sheet deoxidized with GARDOCLEAN S5149 showed less than 10% post-hot water rinse loss of phosphorus for their bottom surfaces, while all but 3 specimens lost greater than 15% of the phosphorus coating weight from their upper surfaces after that step.

[0093] For the 5754-O sheets of Example 4 deoxidized with BONDERITE C-IC 243, all BDT test conditions provided 45 cycles. Also, for the 5754-O sheets deoxidized with BONDERITE C-IC 243, the 3 specimens for the A:B=35:65 condition showed greater than 15% post-hot water rinse loss of phosphorus from both their upper and lower surfaces. Also, in Example 4, for the 5754-O sheets deoxidized with GARDOCLEAN S5149, all but one of the BDT test conditions (PMT=180 F., (A+B) concentrations=0.625 for both the lower and upper surfaces, and A:B=10:90) achieved 45 cycles. In that case, the specimens achieved an average of 39 BDT cycles. Also, for the 5754-O sheets deoxidized with GARDOCLEAN S5149, the 3 specimens for the A:B=35:65 condition showed greater than 15% post-hot water rinse loss of phosphorus from their lower surfaces, and all the specimens lost greater than 15% of the phosphorus coating weight from their upper surfaces after that step.

[0094] The results of Example 4 suggest that, at least for the tested conditions, the deoxidizer formulation and the A:B ratio of the PCOA used in the corresponding steps for the 5754-O and 6022-T4(1) sheets may influence phosphorus retention results after the hot water rinse step. However, the effect of variations in these two process conditions on BDT results appears to be marginal. Overall, in Example 4, good performance was observed in the BDT testing with both the 6022-T4(1) and 5754-O sheets at all process conditions regardless of which of the two deoxidizer formulations were used.

Example 5

[0095] Aluminum alloy sheets were subjected to the procedure and conditions of Example 4, except that in Example 5, a PMT of 270 F. was used in addition to the 210 F. and 240 F. PMT conditions, and the 180 F. PMT condition was used for only one 5754 sheet at a single condition set for GARDOCLEAN S5149 acid deoxidizer. Also, in Example 5, and an additional A:B condition of 25:75 was included for the PCOA. For the Example 5 the aluminum alloy sheets, the (A+B) concentration of the PCOA was either maintained at the same concentration for the upper and lower surfaces, or the (A+B) concentration was less for the upper surface as compared to the lower surface (see Tables 8A and 8B, below). XRF analysis and BDT tests were performed as described above in reference to Example 2.

[0096] The results of the XRF testing of 6022-T4(1) and 5754-O aluminum alloy sheets from Example 5 are provided in Tables 8A and 8B, below. In Tables 8A and 8B, below, each XRF test result represents the average of four replicate test results of four specimens per sheet. Also, in Tables 8A and 8B, below, sheets having a post-drying coat weight of from 0.21 to 3.55 mg/m.sup.2 P are deemed passing (P) results. If an initial XRF result for post-drying phosphorus coating weight was not within 0.21-3.55 mg/m.sup.2 P, that sheet was deemed a failing (F) result (no failing initial XRF results observed for Example 5). Results from re-measurement of phosphorus coating weight by XRF after the post-drying hot deionized water rinse are classified into three categories in Tables 8A and 8B: (1) a reduction in phosphorus coating weight of less than 10%; (2) a reduction in phosphorus coating weight of 10-15%; and (3) a greater than 15% reduction in phosphorus coating weight. Also, in Table 8A, below, a sheet for which XRF testing was not performed is indicated by double dashes (--). The BDT results of specimens of 6022-T4(1) and 5754-O aluminum alloy sheets from Example 5 are provided in Tables 9A and 9B, below.

TABLE-US-00018 TABLE 8A XRF Test Results for BONDERITE C-IC 243 Deox Upper Sheet Surface Lower Sheet Surface Concentration Concentration 5754-O 6022-T4(1) 5754-O 6022-T4(1) (A + B, wt. %) Ratio (A:B) Post-Hot Post-Hot Post-Hot Post-Hot (For Both Upper (For Both Upper Initial Water Initial Water Initial Water Initial Water & Lower Surfaces, & Lower Surfaces, XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Unless Otherwise Unless Otherwise (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) Specified) Specified) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 0.625 25:75 P <10 P <10 (upper) 1.25 (lower) 210 1.25 10:90 P <10 P <10 P <10 P <10 0.625 25:75 P <10 P <10 P <10 P <10 (upper) 1.25 (lower) 240 1.25 10:90 P <10 P <10 P <10 P <10 0.625 25:75 P <10 P <10 P <10 P <10 (upper) 1.25 (lower) 270 0.625 25:75 P <10 P <10 (upper) 1.25 (lower)

TABLE-US-00019 TABLE 8B XRF Test Results for GARDOCLEAN S5149Deox Upper Sheet Surface Lower Sheet Surface Concentration Concentration 5754-O 6022-T4(1) 5754-O 6022-T4(1) (A + B, wt. %) Ratio (A:B) Post-Hot Post-Hot Post-Hot Post-Hot (For Both Upper (For Both Upper Initial Water Initial Water Initial Water Initial Water & Lower Surfaces, & Lower Surfaces, XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF XRF Rinse XRF PMT Unless Otherwise Unless Otherwise (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss (Pass or (% Loss ( F.) Specified) Specified) Fail) of P) Fail) of P) Fail) of P) Fail) of P) 210 1.25 10:90 P >15 P >15 P >15 P >15 0.625 25:75 P <10 P >15 P >15 P >15 (upper) 1.25 (lower) 240 1.25 10:90 P >15 P >15 P >15 P >15 0.625 25:75 P <10 P >15 P >15 P >15 (upper) 1.25 (lower) 270 0.625 25:75 P <10 P <10 P >15 P <10 (upper) 1.25 (lower)

TABLE-US-00020 TABLE 9A BDT Test Results for BONDERITE C-IC 243 Deox Concentration (A + B, wt. %) Concentration Ratio (A:B) (For Both Upper & Lower (For Both Upper & Lower Number of Specimens Failing Prior Surfaces, Unless Otherwise Surfaces, Unless Otherwise to Completing 45 BDT Cycles PMT ( F.) Specified) Specified) 5754-O 6022-T4(1) 180 0.625 (upper) 25:75 0 1.25 (lower) 210 1.25 10:90 0 2 (1) 0.625 (upper) 25:75 0 0 1.25 (lower) 240 1.25 10:90 0 2 (1) 0.625 (upper) 25:75 0 0 1.25 (lower) 270 0.625 (upper) 25:75 0 1.25 (lower)

TABLE-US-00021 TABLE 9B BDT Test Results for GARDOCLEAN S5149 Deox Concentration (A + B, wt. Concentration Ratio %) (A:B) (For Both Upper & (For Both Upper & Number of Specimens Failing Prior to Lower Surfaces, Unless Lower Surfaces, Unless Completing 45 BDT Cycles PMT ( F.) Otherwise Specified) Otherwise Specified) 5754-O 6022-T4(1) 210 1.25 10:90 0 1 (30) 0.625 (upper) 25:75 0 0 1.25 (lower) 240 1.25 10:90 0 1 (30) 0.625 (upper) 25:75 0 0 1.25 (lower) 270 0.625 (upper) 25:75 0 0 1.25 (lower)

[0097] In Tables 9A and 9B, above, each BDT result represents the average of four replicate specimens per sheet. Also, in Tables 9A and 9B, above, BDT results are classified into three categories: (1) all specimens achieving at least 45 cycles of BDT (e.g., no failing specimens); (2) one specimen not achieving 45 BDT cycles; and (3) 2 or more specimens not achieving 45 BDT cycles). In Tables 9A and 9B, in cases where one or more tested specimens did not successfully attain 45 BDT cycles, the average number of cycles that the four tested specimens attained is shown in parentheses. A sheet for which BDT testing was not performed is indicated by double dashes (--) in Table 9A, above.

[0098] In Example 5, for the 6022-T4(1) sheets deoxidized with BONDERITE C-IC 243, all but two of the BDT test conditions (the 2 specimens associated with the A:B=10:90 condition at PMTs of 210 and 240 F.) achieved 45 cycles. In both of those cases, the specimens achieved an average of 1 BDT cycle. Also, for the 6022-T4(1) sheets deoxidized with BONDERITE C-IC 243, all specimens showed less than 10% post-hot water rinse loss of phosphorus from both their upper and lower surfaces. For the 6022-T4(1) sheets deoxidized using GARDOCLEAN S5149, the 2 specimens associated with the A:B=10:90 condition at PMTs of 210 and 240 F. did not achieve 45 cycles, but achieved far greater cycles prior to failure (30 cycles) as compared to the two corresponding 6022-T4(1) sheet specimens deoxidized with BONDERITE C-IC 243 (1 cycle each). Also, for the GARDOCLEAN S5149-deoxidized 6022-T4(1) sheets, all but one of the tested conditions (the specimen associated with the A:B=25:75 condition at PMT=270 F.) showed greater than 15% post-hot water rinse phosphorus loss from both the upper and lower surfaces.

[0099] For the 5754-O sheets deoxidized with BONDERITE C-IC 243, all specimens achieved 45 BDT cycles over all conditions. Also, for the 5754-O sheets deoxidized with BONDERITE C-IC 243, all specimens showed less than 10% post-hot water rinse loss of phosphorus from both their upper and lower surfaces. For the 5754-O sheets deoxidized using GARDOCLEAN S5149, all specimens achieved 45 BDT cycles over all conditions. Also, for the GARDOCLEAN S5149-deoxidized 6022-T4(1) sheets, all specimens exhibited greater than 15% post-hot water rinse phosphorus loss from both the upper and lower surfaces over all the conditions.

[0100] The results of Example 5 suggest that, at least for the tested conditions, the A:B ratio of the PCOA used in the corresponding steps may exert a temperature independent influence bonding performance for 6022-T4(1) sheets, with the effect being more pronounced when BONDERITE C-IC 243 was used for deoxidization as compared to GARDOCLEAN S5149. This effect was not observed in Example 5 for the 5754-O sheets. Also, the Example 5 results suggest that, for both 6022-T4(1) and 5754-O sheets, the choice of acid deoxidizer formulation may influence post-hot water rinse phosphorus retention results for both the upper and lower surfaces. More broadly, results from the experimental work clearly demonstrates that, by adjusting deoxidizer, concentrations, component ratios and PMT, suitable treatment weight and bond durability performance can be achieved.

Example 6

[0101] Several aluminum alloy sheet products (the coils) were produced from both 5xxx and 6xxx alloys in a full-scale plant production trial. The coils were alkaline cleaned by immersion into an alkaline solution (Chemetall Kleen 4010) to remove residual lubricants and general contamination. The alkaline cleaning was performed for a residence time of 4-8 seconds, and at a temperature of 130 F. After the alkaline cleaning, the coils were rinsed with deionized water.

[0102] Following the alkaline cleaning and rinse steps, the coils were deoxidized by immersion in BONDERITE C-IC 243. The deoxidizing was performed for a residence time of 8-16 seconds, and at a temperature of 170 F. After the deoxidization step, the coils were rinsed with deionized water.

[0103] After the deoxidization and rinsing steps, the coils were contacted with an aqueous functionalization solution in the form of a phosphorus-containing organic acid (PCOA) solution maintained at a temperature of 75-90 F. The coils were contacted with the PCOA via a direct roll coating application method (see, e.g., FIG. 2B). The PCOA included a solution mixture of active ingredients including a first monomer component (component A) and a second polymer component (B). Component A was a polymer, as per U.S. Pat. No. 6,167,609, and component B was a copolymer, as per U.S. Pat. No. 6,020,030. The amount of component A exceeded the amount of component B in the solution. Two aqueous functionalization treatment baths were used (Treatment #1 and Treatment #2). Treatment #1 included (1) exposing the top surface of the coil to an aqueous functionalization solution having a total concentration of active ingredients of 0.625 wt. % (i.e., [A+B]=0.625 wt. %) at an A:B ratio of 35:65, and (2) exposing the bottom surface of the coil to an aqueous functionalization solution having a total concentration of active ingredients of 0.625 wt. % at an A:B ratio of 25:75. Treatment #2 included exposing the top surface of the coil to an aqueous functionalization solution having a total concentration of active ingredients of 0.4 wt. % at an A:B ratio of 50:50, and (2) exposing the bottom surface of the sheet products to an aqueous functionalization solution having a total concentration of active ingredients of 0.4 wt. % at an A:B ratio of 50:50. The aqueous functionalization treatment used for each coil is indicated in Table 10A, below.

[0104] After roll coating the coils with the aqueous functionalization solutions, the coils were then dried. The drying included reaching a peak metal temperature (PMT) of about 240 F. for all of the coils. Production data, including the gauge of the coil, the width of the coil, the total weight of coil, the total length of the coil, the treatment speed, and the total time to treat the each coil is given in Tables 10A-10B, below.

TABLE-US-00022 TABLE 10A Example 6 Production Data Aqueous Coil Coil Functionalization Gauge Width Coil No. Alloy Temper Treatment No. (in) (in) 1 6022 T43 Treatment #1 0.0315 72 2 6022 T4E32 Treatment #1 0.037 69.8 3 6022 T43 Treatment #2 0.047 69.1 4 5182 O Treatment #1 0.0645 54 5 5182 O Treatment #1 0.078 58 6 6111 T4 Treatment #1 0.098 72 7 6111 T4 Treatment #1 0.137 69.566 8 6111 T4 Treatment #2 0.126 64.29 9 6022 T4E32 Treatment #2 0.037 69.7

TABLE-US-00023 TABLE 10B Example 6 Production Data Total Weight of Total Length of Treatment Total Treatment Coil Coil Speed Time Coil No. (lbs) (ft) (fpm) (min) 1 17,635 6,679 300 22.3 2 9,205 3,037 300 10.1 3 12,966 3.409 300 11.4 4 6,800 1,704 300 5.7 5 15,630 3,005 300 10 6 14,965 1,812 300 6 7 16,315 1,474 150 9.8 8 17,758 1,883 150 12.6 9 8,500 2,806 300 9.4

[0105] Initial X-ray fluorescence (XRF) analysis for phosphorus coating weight was performed following completion of the drying. The XRF specimens were taken at the head and tail of each of the top and bottom of the sheet products. After the initial XRF analysis, the initial XRF specimens were rinsed in deionized water at 180 F. by immersion for 5 seconds, and the XRF measurement was performed again on the specimens. Results from the XRF analysis are given in Table 10C-10D, below. In this regard, Table 10C gives the XRF results in mg/m.sup.2, whereas Table 10D gives percentage of phosphorus loss after the deionized water rinse, relative to the results given in Table 10C.

TABLE-US-00024 TABLE 10C XRF Analysis Results (in mg/m.sup.2) After Coating Top Bottom Coil No. Head Tail Head Tail 1 N/A 2.43 2.24 2.20 2 2.42 2.30 1.97 1.89 3 1.88 2.27 N/A 1.63 4 2.40 2.32 1.39 1.65 5 2.24 2.32 1.58 1.55 6 2.08 2.27 1.57 1.52 7 2.26 2.17 1.50 1.47 8 1.70 1.82 1.15 1.36 9 1.72 1.71 1.20 1.19

TABLE-US-00025 TABLE 10D XRF Analysis Results (in % phosphorus loss) After Rinsing Top Bottom Coil No. Head Tail Head Tail 1 N/A 31 31 29 2 34 32 17 26 3 24 25 N/A 16 4 26 20 17 14 5 21 23 14 17 6 22 25 16 26 7 27 22 14 16 8 32 25 29 22 9 33 40 28 34

[0106] Specimens from the coils were adhesively bonded and then subjected to bond durability testing (BDT) according to an automotive industry standard cyclical corrosion exposure test. This bond durability testing included a combination of applied lap shear stress and environmental exposure (the BDT test). The bond durability tests were performed with specimens taken at both the head and tail of the coils for an average of 3 specimens, the results of which are given in Table 10E, below.

TABLE-US-00026 TABLE 10E Example 6 Average Bond Durability Cycles Survived Coil No. Head Tail 1 45 45 2 45 45 3 45 45 4 45 45 5 45 45 6 45 45 7 45 45 8 45 45 9 45 45

[0107] Whereas particular embodiments of this disclosure have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations on the details of the present disclosure may be made without departing from the scope of the disclosure as defined in the appended claims.