High Temperature Thermo-Acoustic Barrier Material with Low Smoke and Odor
20220002204 · 2022-01-06
Inventors
Cpc classification
C23C28/00
CHEMISTRY; METALLURGY
F01N13/16
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60R13/0815
PERFORMING OPERATIONS; TRANSPORTING
F01N13/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B60R13/0869
PERFORMING OPERATIONS; TRANSPORTING
F01N2510/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
F01N13/14
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
A thermal barrier material for use in shielding components of a vehicle from hot exhaust surfaces includes 35 to 53% of a plurality of clays by weight and a remainder including magnesium silicate, alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide. A sample of the thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm.sup.3 as measured according to the ISO 5659-2:2006(E) standard.
Claims
1. A thermal barrier material for use in shielding components of a vehicle from hot surfaces comprising: 35 to 53% of a plurality of clays by weight; a remainder comprising: magnesium silicate, alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, wherein a sample of the thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm3 as measured according to the ISO 5659-2:2006(E) standard.
2. The thermal barrier material of claim 1, wherein the sample of the thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 2 g/cm3 as measured according to the ISO 5659-2:2006(E) standard.
3. The thermal barrier material of claim 1, wherein the sample of the thermal barrier material produces less than 4 ppm of 1-butanal gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
4. The thermal barrier material of claim 1, wherein the sample of the thermal barrier material produces no detected 1-butanal gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
5. The thermal barrier material of claim 1, wherein the sample of the thermal barrier material produces less than 150 ppm Dimethoxymethane gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
6. The thermal barrier material of claim 1, wherein the plurality of clays comprises: 2 to 5% of aluminum phyllosilicate clay by weight; 8 to 23% of hydrous aluminum silicate by weight; 12 to 18% of hydrous magnesium silicate by weight; and 4 to 7% of phyllosilicate by weight.
7. The thermal barrier material of claim 1 wherein the sample of the thermal barrier material further produces about 55 ppm Dimethoxymethane gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
8. The thermal barrier material of claim 1, wherein the remainder comprises: 8 to 23% of magnesium silicate by weight; 17 to 43% of alumina trihydrate by weight; 2 to 6% of alumino-borosilicate glass by weight; 6 to 8.5 of rock wool by weight; 1 to 7% of basalt fiber by weight; 0.05 to 1.5% of, acrylamide copolymer coagulant by weight; 0.05 to 1.2% of acrylic latex by weight; 0.01 to 0.05% of fatty alcohol alkoxylate by weight; and 0.5 to 1.5% of anionic polyacrylamide by weight.
9. The thermal barrier material of claim 1, wherein the sample of the thermal barrier material does not ignite when exposed to a temperature of 650° Celsius in a furnace.
10. A thermal barrier material for use in shielding components of a vehicle from hot surfaces comprising: 26% to 42% of a plurality of clays by weight; a remainder comprising: magnesium silicate, alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, wherein a sample of the thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm3 as measured according to the ISO 5659-2:2006(E) standard.
11. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 2 g/cm3 as measured according to the ISO 5659-2:2006(E) standard.
12. The thermal barrier material of claim 10, wherein the remainder comprises: 8 to 23% of magnesium silicate by weight; 17 to 43% of alumina trihydrate by weight; 2 to 6% of alumino-borosilicate glass by weight; 6 to 8.5 of rock wool by weight; 1 to 7% of basalt fiber by weight; 0.05 to 1.5% of, acrylamide copolymer coagulant by weight; 0.05 to 1.2% of acrylic latex by weight; 0.01 to 0.05% of fatty alcohol alkoxylate by weight; and 0.5 to 1.5% of anionic polyacrylamide by weight.
13. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces less than 4 ppm of 1-butanal gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
14. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces no detected 1-butanal gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
15. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces less than 100 ppm Dimethoxymethane gas as measured by Gas Chromatography (GC) and Mass Spectrometry (MS).
16. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces less than 100 ppm CO gas as measured according to ASTM 800 standards.
17. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces about 46 ppm CO gas as measured according to ASTM 800 standards.
18. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces less than 700 ppm CO2 gas as measured according to ASTM 800 standards.
19. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material produces about 599 ppm CO2 gas as measured according to ASTM 800 standards.
20. The thermal barrier material of claim 10, wherein the sample of the thermal barrier material does not ignite when exposed to a temperature of 650° Celsius in a furnace.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE DRAWINGS
[0024] Reference will now be made in more detail to the drawing figures, wherein like reference numerals indicate like parts throughout the several views.
[0025] An acoustic absorption layer 18 is secured to the thermal barrier layer 17 on one side thereof. The acoustic absorption layer 18 can be secured to the thermal barrier layer by any appropriate means such as with an adhesive for example. One preferred method of securing the layers together is shown in
[0026] The thermal barrier layer 17 is initially applied in the form of a slurry onto an upwardly facing surface of the acoustic absorption layer 18. The slurry flows partially into the holes 19 as perhaps best illustrated in
[0027] The acoustic absorption layer 18 may be formed of any material that performs the function of absorbing sound before it enters the passenger compartment of a vehicle. In the preferred embodiment, the acoustic absorption layer 18 is made of a non-woven fiberglass sound absorbing material such as that available from Owens Corning Corporation of Toledo, Ohio and other suppliers. Other possible materials that may be suitable for the acoustic absorption layer include, without limitation, cotton and organic sound absorbing batts, silica fiber mats, and sound absorbing foam to mention a few.
[0028] While the thermo-acoustic barrier is shown as a flat sheet or tile in
[0029] As detailed below, it has been found through experimentation that the smoke and unpleasant odors often produced by prior art thermal barriers (of which consumers complain) result from the burn-off of organic binders and other organic compounds present in the material of these barriers. In contrast, the materials from which the thermal barrier of the present subject matter is made are very low in organic compounds and binders compared to prior art thermal barriers. In one preferred embodiment, the thermal barrier of this present subject matter may be made as follows.
MAKING THE THERMAL BARRIER
[0030] Table 1 below shows the ingredients used to make the example TI650 and TI1000 (TI1K) thermal barrier materials of the present subject matter and, for each ingredient, the percent-by-weight of the ingredient used in a slurry to be made into the thermal barrier material in a paper making machine.
TABLE-US-00001 TABLE 1 TI650 TI1K magnesium silicate 17-23 8-12 aluminum phyllosilicate 2-5 2-5 clay hydrous aluminum silicate 17-23 8-12 hydrous magnesium silicate 12-18 12-18 (talc) phyllosilicate (mica) 4-7 4-7 alumina trihydrate 17-23 35-43 alumino-borosilicate glass 2-6 2-6 dye 1-1.5 .5-1.5 rock wool 6-8 6-8.5 basalt fiber 1-6 4-7 acrylamide copolymer .05-1.5 .05-1.5 coagulant acrylic latex .07-1.2 .05-.95 fatty alcohol alkoxylate .01-.05 .01-.05 anionic polyacrylamide .5-1.5 .5-1.5 cellulose fiber 1-1.8 0
[0031] The TI650 and TI1000 (TI1K) are merely example embodiments of the present subject matter and should not be construed to limit the scope of the present subject matter to these example embodiments. Various modifications and substitutions may be made. For instance, several of the ingredients listed in Table 1 above may be generally considered clays in the art, such as aluminum phyllosilicate clay, hydrous aluminum silicate, phyllosilicate (mica), and hydrous magnesium silicate (talc). These clays may be generally substituted in their proportions or replaced altogether with other clays suitable for use in thermally shielding hot surfaces, such as exhaust components of a vehicle. Such variations and/or substitutions in the proportions of the ingredients may achieve nuanced variations in the performance of the overall thermal barrier material without substantially compromising the net objective of reducing smoke and odor when exposed to heat when compared with thermal barrier materials of the prior art.
[0032] A third example thermal barrier material that, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm.sup.3 as measured according to the ISO 5659-2:2006(E) standard may include 35 to 53% of a plurality of clays by weight and a remainder including one or more of magnesium silicate, alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide. As previously discussed, the clays may include one or more of aluminum phyllosilicate clay, hydrous aluminum silicate, phyllosilicate (mica), and hydrous magnesium silicate (talc). Other clays suitable for use in thermal shielding for vehicles may be also be substituted or use in conjunction with the clays previously discussed. Table 2 below shows the ingredients used to make the third example thermal barrier material of the present subject matter and, for each ingredient, the percent-by-weight of the ingredient used in a slurry to be made into the thermal barrier material in a paper making machine.
Third Example Thermal Barrier Material
[0033]
TABLE-US-00002 TABLE 2 one or more of: aluminum phyllosilicate clay, 35-53 hydrous aluminum silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) one or more of: magnesium silicate, alumina 47-65 trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, dye, cellulose fiber
[0034] A fourth example thermal barrier material that, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm.sup.3 as measured according to the ISO 5659-2:2006(E) standard may include 26% to 42% of a plurality of clays by weight and a remainder including one or more of magnesium silicate, alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide. As previously discussed, the clays may include one or more of aluminum phyllosilicate clay, hydrous aluminum silicate, phyllosilicate (mica), and hydrous magnesium silicate (talc). Other clays suitable for use in thermal shielding for vehicles may be also be substituted or use in conjunction with the clays previously discussed. Table 3 below shows the ingredients used to make the fourth example thermal barrier material of the present subject matter and, for each ingredient, the percent-by-weight of the ingredient used in a slurry to be made into the thermal barrier material in a paper making machine.
Fourth Example Thermal Barrier Material
[0035]
TABLE-US-00003 TABLE 3 one or more of: aluminum phyllosilicate 26-42 clay, hydrous aluminum silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) one or more of: magnesium silicate, 58-74 alumina trihydrate, alumino-borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, dye
[0036] Additionally, the previously-disclosed example embodiments of the TI650 and TI1000 (TI1K) thermal barrier materials may be combined and configured as desired to form a fifth example thermal barrier material as shown in Table 4 below. Like the previous example thermal barrier materials, the fifth example thermal barrier material, when exposed to a temperature of 400° Celsius, produces smoke having a density less than 5 g/cm.sup.3 as measured according to the ISO 5659-2:2006(E) standard. Table 4 below shows the ingredients used to make the fifth example thermal barrier material of the present subject matter and, for each ingredient, the percent-by-weight of the ingredient used in a slurry to be made into the thermal barrier material in a paper making machine.
Fifth Example Thermal Barrier Material
[0037]
TABLE-US-00004 TABLE 4 magnesium silicate 8-23 aluminum phyllosilicate clay 2-5 hydrous aluminum silicate 8-23 hydrous magnesium silicate (talc) 12-18 phyllosilicate (mica) 4-7 alumina trihydrate 17-43 alumino-borosilicate glass 2-6 dye 0.5-1.5 rock wool 6-8.5 basalt fiber 1-7 acrylamide copolymer coagulant .05-1.5 acrylic latex .05-1.2 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 0-1.8
[0038] Additional example thermal barrier material compositions in accordance with the present subject matter are provided in Tables 5-11 below:
Sixth Example Thermal Barrier Material
[0039]
TABLE-US-00005 TABLE 5 one or more of: aluminum phyllosilicate 26-42 clay, hydrous aluminum silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) magnesium silicate 8-23 alumina trihydrate 17-43 alumino-borosilicate glass 2-6 dye 0.5-1.5 rock wool 6-8.5 basalt fiber 1-7 acrylamide copolymer coagulant .05-1.5 acrylic latex .05-1.2 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 0-1.8
Seventh Example Thermal Barrier Material
[0040]
TABLE-US-00006 TABLE 6 one or more of: aluminum phyllosilicate clay, 35-53 hydrous aluminum silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) magnesium silicate 8-23 alumina trihydrate 17-43 alumino-borosilicate glass 2-6 dye 0.5-1.5 rock wool 6-8.5 basalt fiber 1-7 acrylamide copolymer coagulant .05-1.5 acrylic latex .05-1.2 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 0-1.8
Eighth Example Thermal Barrier Material
[0041]
TABLE-US-00007 TABLE 7 one or more of: aluminum phyllosilicate clay, 26-53 hydrous aluminum silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) magnesium silicate 17-23 alumina trihydrate 17-43 alumino-borosilicate glass 2-6 dye 0.5-1.5 rock wool 6-8.5 basalt fiber 1-7 acrylamide copolymer coagulant .05-1.5 acrylic latex .05-1.2 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 0-1.8
Ninth Example Thermal Barrier Material
[0042]
TABLE-US-00008 TABLE 8 aluminum phyllosilicate clay, hydrous 26-42 aluminum silicate, phyllosilicate (mica), and hydrous magnesium silicate (talc) magnesium silicate 8-12 alumina trihydrate 35-43 alumino-borosilicate glass 2-6 dye .5-1.5 rock wool 6-8.5 basalt fiber 4-7 acrylamide copolymer coagulant .05-1.5 acrylic latex .05-.95 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 0
Tenth Example Thermal Barrier Material
[0043]
TABLE-US-00009 TABLE 9 aluminum phyllosilicate clay, hydrous 35-53 aluminum silicate, phyllosilicate (mica), and hydrous magnesium silicate (talc) magnesium silicate 17-23 alumina trihydrate 17-23 alumino-borosilicate glass 2-6 dye 1-1.5 rock wool 6-8 basalt fiber 1-6 acrylamide copolymer coagulant .05-1.5 acrylic latex .07-1.2 fatty alcohol alkoxylate .01-.05 anionic polyacrylamide .5-1.5 cellulose fiber 1-1.8
Eleventh Example Thermal Barrier Material
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TABLE-US-00010 TABLE 10 aluminum phyllosilicate clay, hydrous aluminum 26-42 silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) magnesium silicate, alumina trihydrate, alumino- 58-74 borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, dye
Twelfth Example Thermal Barrier Material
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TABLE-US-00011 TABLE 11 aluminum phyllosilicate clay, hydrous aluminum 35-53 silicate, phyllosilicate (mica), or hydrous magnesium silicate (talc) magnesium silicate, alumina trihydrate, alumino- 47-65 borosilicate glass, rock wool, basalt fiber, acrylamide copolymer coagulant, acrylic latex, fatty alcohol alkoxylate, or anionic polyacrylamide, dye, cellulose fiber
[0046] Except for the basalt fibers, the fibers and clays of the example thermal barrier material compositions in Tables 1-11 may be combined with water (between 7 and 50° C.) into a slurry using a pulper. To maintain the length of the basalt fibers, they may be added directly to the mixing chest and homogenized into the mixing stock to avoid the shear forces generated in the pulper. The latex is then added and precipitated onto the fiber and fillers. The resulting slurry is spread onto the conveyor belt at the wet end of a traditional Fourdrinier paper making machine forming a wet web of fibers. If the thermal barrier material is to be combined with an acoustic absorption barrier, the slurry may be spread onto a thin sheet of the acoustic absorption material, which may have been prepared with holes to facilitate binding the two layers together. In the machine, the wet web is dewatered and dried. The resulting web can then be cut into desired shapes and molded if desired to fit into areas where it is to be used.
Testing
[0047] Most of the tests described below were carried out according to the corresponding established industry method (typically an ASTM standard). However, due to the subjective nature of the offensive odor testing, internal testing methods were developed that quantified the intensity and offensiveness of odors produced by prior art thermal barrier materials and by thermal barrier materials of the present subject matter. An objective test for the presence of chemicals known to produce offensive odors also was carried out. In addition, the thermal masking tests were conducted using an internal testing method historically used to assess various thermal conduction properties of heat shield insulating material. These tests are detailed below.
1. Cold Formability and Vibration Testing
[0048]
[0049] After each sample was molded into a bowl shape as described, it was heated in a furnace to 400° C. for 30 minutes and then placed in a tabletop shaker 26 (
[0050] To determine loss of mass due to dusting compared to prior art thermal barrier materials, die-cut and cold formed thermal barrier samples of the present subject matter and samples of prior art thermal barrier materials were tested. In each case, a sample was weighed, heated to 400° C. for 30 minutes, placed in a table top shaker for 5 minutes, and then weight again. Any loss in weight is due to dusting of material away from the sample during the heating and shaking process.
[0051] In stark contrast, the total loss of weight due to dusting for the TI1000 (TI1K) thermal barrier sample under the same test conditions was a mere 0.14% with about half of the loss (0.06%) being due to die-cut sample loss. For the TI650 sample of the present subject matter, total loss of weight was still a mere 0.14% but the great majority of the loss (0.12%) was due to dusting losses from the die-cut sample. The cold formed sample lost only 0.02% of its weight during the test. The conclusion is that heat barriers formed according to the present subject matter exhibit far less weight loss due to dusting than do the prior art heat barriers tested.
2. Smoke and Offensive Odor Test
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[0053] The same test was carried out with a sample of the TI1000 (TI1K) thermal barrier sample 29 made according to the present subject matter and a prior art thermal barrier with similar specifications. Again, the panel members rated the intensity and offensiveness of odors produced by the sample just as they had done with the prior art sample 28. The results of this test are shown in the chart 36 of
[0054] In contrast, the intensity 38, 42 of odors produced by the TI1000 (TI1K) and TI650 samples made according to the present subject matter (chart 41) rated very low at just above zero for the full duration of the test. Offensiveness 37, 41 of these odors for these samples rated between 1 and 1.5 at the beginning, ramping down to just above zero at one minute into the test. Thus, thermal barriers made according to the present subject matter showed a drastic reduction in intensity and offensiveness of odors produced at high temperatures compared to those produced by the prior art thermal barrier.
[0055] In addition to these subjective tests, an objective odor evaluation was commissioned by an outside laboratory. The laboratory tested liberated gases from a sample of prior art thermal barrier material and a sample of thermal barrier material made according to the present subject matter when heated as described above. Gas Chromatography (GC) and Mass Spectrometry (MS) techniques were used to determine the presence of 1-butanol and Dimethoxymethane, both deemed by most humans to be associated with and indicative of offensive odors.
[0056] As can be seen from the summary chart of
[0057]
[0058] The density of produced smoke for the barriers of the present subject matter also was measured according to the ISO 5659-2:2006(E) standard. The measured density for both the TI650 and the TI1000 (TI1K) samples was less than 5 g/cm.sup.3, less than 2 g/cm.sup.3, and more specifically measured to be about 0.88 g/cm.sup.3. Such smoke densities are considered barely detectable. As can be seen in
3. Shock Flame Testing
[0059] A prior art thermal barrier material and the TI1000 (TI1K) thermal barrier material of the present subject matter were tested to determine their tendency to ignite at high temperatures. These two products have similar maximum temperature specifications of 1000° C. The test setup is shown in
[0060] Similarly, a prior art thermal barrier material and the TI650 thermal barrier 15 material of the present subject matter were tested for ignition using the same procedure. These two products have similar maximum temperature specifications of 650° C. Again, the two samples were placed in a furnace pre-heated to 650° C. and observed. As shown in the photograph of
4. Thermal Mapping Tests
[0061] Prior art thermal barriers and thermal barriers of the present subject matter were tested to determine the thermal conductivity of the material. This test is sometimes referred to as a thermal mapping test and was carried out according to ASTM standard F433. In the test, a sample of interest was placed directly on a pre-heated 400° C. hotplate. An infrared thermometer was used to map the rise in temperature of the top (exposed) side of the sample. The test was conducted for samples of thickness 0.8 mm and 1.0 mm for each of a prior art thermal barrier material, the TI650 barrier of the present subject matter, and the TI1000 (TI1K) barrier of the present subject matter. The results are shown in
[0062] The test results are shown numerically on the left in
5. Toxicity of Generated Gases Test
[0063] A sample of prior art thermal barrier material and a sample of the TI1000 (TI1K) barrier material of the present subject matter were tested according to ASTM standard 800 relating to Measurement of Gases Present or Generated During Fires. Specifically, gasses produced by these samples when burned were collected and analyzed using Fourier Transform Infrared Spectroscopy (FTIR) for toxic compounds contained in the resulting smoke. The testing measured the presence of the following compounds: CO; CO.sub.2; HCL; HCN; HBr; HF; NO; NO.sub.2; and SO.sub.2. With the exception of carbon monoxide (CO) and carbon dioxide (CO.sub.2), none of the toxic compounds were present. As for CO and CO.sub.2 levels in the gasses were determined and are presented in the table of
6. Summary of Testing
[0064]
[0065] A horizontal flame spread test was conducted on the two samples according to SAE J369 testing standards. In this test, each sample was suspended in a horizontal orientation and a Bunsen burner was placed beneath one end of the sample. If the sample ignited and the flame did not self-extinguish, a rate at which the flame was observed to spread would be tabulated. In this test, the prior art sample did not ignite (DNI) and the sample of the TI1000 (TI1K) thermal barrier also did not ignite.
[0066] A compression/recovery test was conducted on both samples according to ASTM F36K standards using an Armstrong Static Indentation Machine. This test measures the ability of the material to absorb compressive forces and, once compressed, how well the material returns to its original caliper. The thickness of the sample is measured and then the sample is subjected to an extreme load for a specified time sufficient to compress the material. The load is then removed and the material is allowed to rebound partially to its original thickness. The final thickness is then measured. The rebounded thickness divided by the original thickness represents the compression/rebound measurement expressed as a percentage. Greater rebound is desirable. In these tests, the prior art sample rebounded by 16/28 or 57% while the sample of the present subject matter rebounded by 20/27 or 74%. Thus, a thermal barrier of the present subject matter is more tolerant of compressive loads than the thermal barrier of the prior art.
[0067] The thermal conductivity of each sample was measured according to the procedure outlined above. The results are tabulated again in the summary chart of
[0068]
[0069] The foregoing disclosure has been set forth merely to illustrate the present subject matter and is not intended to be limiting. Examples have been selected merely to further illustrate features, advantages, and other details of the present subject matter. While examples may serve this purpose, the particular material compositions, amounts, proportions, and other conditions should not be construed in a limiting manner. Since modifications of the disclosed embodiments incorporating the spirit and substance of the present subject matter may occur to persons skilled in the art, the present subject matter should be construed to include everything within the scope of the appended claims and equivalents thereof.