Iron-based metal powder for ultra-high-speed laser cladding, its preparation method and its application

Abstract

An iron-based metal powder for ultra-high-speed laser cladding comprising chemical composition and mass percentage of the metal powder of: C 0.6?1.0%, Cr 17.0?20.0%, Ni 5.0?6.5%, Mn 2.0?4.0%, Mo 1.0?1.5%, Ti 4.0?6.0%, B 1.0?1.5%, N 0.08?0.15%, Si?0.5%, P?0.030%, S?0.030%, balance of Fe and unavoidable impurities, wherein the particle size of the metal powder is 15?65 ?m, the fluidity is 16?20 s/50 g.

Claims

1. An ultra-high-speed laser cladding process using an iron-based metal powder, comprising: machining a surface of substrate; wiping the surface of substrate with acetone to remove surface grease; carrying out laser cladding path planning according to a geometry of the surface of substrate, formulating process parameters; and using Computerized Numerical Control (CNC) machine tools to machine the repaired substrate surface to obtain the required size; wherein a semiconductor laser cladding system is used to clad and repair the surface of substrate with the following process parameters: laser power 1500?2500 W, spot diameter 0.8?1.2 mm, powder feeding rate 2?5 kg/h, laser scanning rate 330?830 m/min, overlap rate 40%?70%, and single layer cladding thickness 250?500 ?m, wherein a laser cladding head with an argon gas protection function is used, and wherein an argon gas flow rate of 8?20 L/min is used, wherein the iron-based metal powder comprises: C at 0.6?1.0%, Cr at 18.0?20.0%, at Ni 5.0?6.5% at Mn 2.0?4.0%, at Mo 1.0?1.5%, Ti at 4.0?6.0%, B at 1.0?1.5%, N at 0.08?0.15%, Si at ?0.5%, P at ?0.030%, S at ?0.030%, balance of Fe and unavoidable impurities.

2. The ultra-high-speed laser cladding process using the iron-based metal powder according to claim 1, wherein a sphericity of the powder is greater or equal to 90%.

3. The ultra-high-speed laser cladding process using the iron-based metal powder according to claim 2, wherein a particle size distribution of the powder is 15?65 ?m.

4. The ultra-high-speed laser cladding process using the iron-based metal powder according to claim 3, wherein a D50 of the powder is 25?40 ?m.

5. The ultra-high-speed laser cladding process using the iron-based metal powder according to claim 4, wherein the powder has a fluidity of 16?20 s/50 g and an oxygen content is less than or equal to 200 ppm.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) The present disclosure will be further described in conjunction with Examples and Comparative Examples. The mass fractions of each element in the Examples and Comparative Examples are shown in Table 1, and the performance parameters are shown in Table 2. The main process parameters and cladding quality used in the Examples and Comparative Examples are shown in table 3.

(2) TABLE-US-00001 TABLE 1 shows the composition (mass fraction, %) of iron-based metal powder for ultra-high-speed laser cladding. Examples C Cr Ni Mn Mo Ti B Si P, S N Fe Example 1 0.8 19.0 5.65 3.2 1.2 5.0 1.2 0.1 ?0.03 0.1 Bal. Example 2 0.7 18.0 5.8 3.1 1.4 5.5 1.4 0.1 ?0.03 0.1 Bal. Comparative 0.8 19.0 5.65 3.2 1.2 5.0 1.2 0.1 ?0.03 0.1 Bal. Example 1 Comparative 0.8 19.0 5.65 3.2 1.2 5.0 1.2 0.1 ?0.03 0.1 Bal. Example 2

(3) TABLE-US-00002 TABLE 2 shows the performance parameters (mass fraction, %) of iron-based metal powder for ultra-high-speed laser cladding. Examples Particle ?m Fluidity s/50 Gsphericity % D.sub.50/?m Example 1 15~65 18 91 32 Example 2 15~65 16 95 34 Comparative 50~150 13 89 95 Example 1 Comparative 15~65 18 91 32 Example 2

(4) TABLE-US-00003 TABLE 3 shows the comparison between ultra-high-speed laser cladding and traditional laser cladding. Laser Beam Equipment Laser scanning diameter/ Dilution Examples model power/W rate/mm/s mm rate Cladding layer quality Example 1 High-speed 1600 500 1 2% The surface quality of the cladding cladding layer is good, equipment forming a metallurgical bond Example 2 High-speed 1550 417 1 2% The surface quality of the cladding cladding layer is good, equipment forming a metallurgical bond Comparative Traditional 2250 12 3 25% The surface quality of the Example 1 cladding cladding layer is good, equipment forming a metallurgical bond Comparative Traditional 5000 417 3 The surface quality of the Example 2 cladding cladding layer is poor, and equipment the substrate and the powder have not formed a metallurgical bond

Example 1

(5) Optionally, a method for preparing the above-mentioned powder is characterized in that: composition of raw materials is alloyed and proportioned, and then vacuum smelting is carried out, and a vacuum degree of a melting chamber is set to 10.sup.?1?10.sup.?2 Pa, the powder is made by gas atomization method, an argon pressure of powder spraying gas is set to 1.2?3.8 MPa. After receiving the powder, particle size screening is performed, and the metal powder in the particle size range of 15?65 ?m is selected through screening, to obtain iron-based metal powder for ultra-high-speed laser cladding.

(6) Optionally, an iron-based metal powder is provided, the mass fraction of each element is: C 0.8%, Cr 19.0%, Ni 5.65%, Mn 3.2%, Mo 1.2%, Ti 5.0%, B 1.2%, N 0.09%, Si?0.5%, P?0.030%, S?0.030%, balance of Fe and unavoidable impurities.

(7) The metal powder has a particle size of 15?65 ?m, a fluidity is 18 s/50 g, a sphericity is greater than or equal to 91%, and a D50 is 32 ?m.

(8) Optionally, the powder contains 160 ppm oxygen. The hollow powder rate is less than 1%.

(9) Subsequently, apply the sieved powder, use ultra-high-speed laser cladding technology, and match the corresponding process to repair the surface of substrate.

(10) Optionally, the repair method is to machine the surface of substrate.

(11) Wipe the surface of mold to be repaired with acetone to remove surface grease.

(12) Carry out the path planning of ultra-high-speed laser cladding according to a geometry of the surface of substrate and formulate process parameters.

(13) Use semiconductor laser cladding system to clad and repair the surface of substrate, using the above process parameters: laser power 1700 W, spot diameter 1 mm, powder feeding rate 2.4 kg/h, laser scanning rate 500 mm/s, overlap rate 55%, and single layer cladding thickness 320 ?m, the laser cladding head has an argon gas protection function, and the argon gas flow rate is 10 L/min.

(14) CNC machine tools are used to machine the repaired substrate surface to obtain the required size and good surface properties.

Example 2

(15) Optionally, a method for preparing the above-mentioned powder is characterized in that: composition of raw materials is alloyed and proportioned, and then vacuum smelting is carried out, and a vacuum degree of a melting chamber is set to 10.sup.?1?10.sup.?2 Pa, the powder is made by gas atomization method, an argon pressure of powder spraying gas is set to 1.2?3.8 MPa. After receiving the powder, perform particle size screening, and the metal powder in the particle size range of 15?65 ?m is selected through screening to obtain iron-based metal powder for ultra-high-speed laser cladding.

(16) Optionally, an iron-based metal powder is provided, the mass fraction of each element is: C 0.7%, Cr 18.0%, Ni 5.8%, Mn 3.1%, Mo 1.4%, Ti 5.5%, B 1.2%, N 0.09%, Si?0.5%, P?0.030%, S?0.030%, balance of Fe and unavoidable impurities.

(17) The metal powder has a particle size of 15?65 ?m, a fluidity is 18 s/50 g, a sphericity is greater than or equal to 95%, and a D50 is 34 ?m.

(18) Optionally, the powder contains 160 ppm oxygen. The hollow powder rate is less than 1%.

(19) Apply the sieved powder, use ultra-high-speed laser cladding technology, and match the corresponding process to repair the surface of substrate.

(20) Optionally, the repair method is to machine the surface of substrate.

(21) Wipe the surface of mold to be repaired with acetone to remove surface grease.

(22) Carry out the path planning of ultra-high-speed laser cladding according to a geometry of the surface of substrate and formulate process parameters.

(23) Use semiconductor laser cladding system to clad and repair the surface of substrate, using the above process parameters: laser power 1550 W, spot diameter 1 mm, powder feeding rate 2.2 kg/h, laser scanning rate 417 mm/s, overlap rate 60%, and single layer cladding thickness 300 ?m, the laser cladding head has an argon gas protection function, and the argon gas flow rate is 10 L/min.

(24) CNC machine tools are used to machine the repaired substrate surface to obtain the required size and good surface properties.

Comparative Example 1

(25) Optionally, a method for preparing the above-mentioned powder is characterized in that: composition of raw materials is alloyed and proportioned, and then vacuum smelting is carried out, and a vacuum degree of a melting chamber is set to 10.sup.?1?10.sup.?2 Pa, the powder is made by gas atomization method, an argon pressure of powder spraying gas is set to 1.2?3.8 MPa, after receiving the powder, perform particle size screening, and the metal powder in the particle size range of 50?150 ?m can be selected through screening to obtain iron-based metal powder for ultra-high-speed laser cladding.

(26) Optionally, an iron-based metal powder with the same composition and content as in Example 1 comprises mass fraction of each element as follow: C 0.8%, Cr 19.0%, Ni 5.65%, Mn 3.2%, Mo 1.2%, Ti 5.0%, B 1.2%, N 0.09%, Si?0.5%, P?0.030%, S?0.030%, balance of Fe and unavoidable impurities.

(27) The metal powder has a particle size of 50?150 ?m, a fluidity is 13 s/50 g, a sphericity is greater than or equal to 89%, and a D50 is 95 ?m.

(28) Optionally, the powder contains 190 ppm oxygen. The hollow powder rate is less than 1%.

(29) Apply the sieved powder, use ultra-high-speed laser cladding technology, and match the corresponding process to repair the surface of substrate.

(30) Optionally, the repair method is to machine the surface of substrate.

(31) Wipe the surface of mold to be repaired with acetone to remove surface grease.

(32) Carry out traditional laser cladding path planning according to a geometry of the surface of substrate, and formulating process parameters.

(33) Use semiconductor laser cladding system to clad and repair the surface of substrate, using process parameters: laser power 2250 W, spot diameter 3 mm, powder feeding rate 2.4 kg/h, laser scanning rate 12 mm/s, overlap rate 55%, and single layer cladding thickness 980 ?m, the laser cladding head has an argon gas protection function, and the argon gas flow rate is 10 L/min.

(34) CNC machine tool is used to machine the repaired substrate surface to obtain the required size and good surface properties, but the cladding layer dilution rate is high, and the alloy element content of the cladding layer is significantly lower than that of Example 1 and the powder composition.

Comparative Example 2

(35) Optionally, a method for preparing the above-mentioned powder is provided is characterized in that: composition of raw materials is alloyed and proportioned, and then vacuum smelting is carried out, and a vacuum degree of a melting chamber is set to 10.sup.?1?10.sup.?2 Pa, the powder is made by gas atomization method, an argon pressure of powder spraying gas is set to 1.2?3.8 MPa. After receiving the powder, perform particle size screening, and the metal powder in the particle size range of 15?65 ?m is selected through screening, to obtain iron-based metal powder for ultra-high-speed laser cladding.

(36) Optionally, An iron-based metal powder with the same composition and content as in Example 1 is provided with the mass fraction of each element as follow: C 0.8%, Cr 19.0%, Ni 5.65%, Mn 3.2%, Mo 1.2%, Ti 5.0%, B 1.2%, N 0.09%, Si?0.5%, P?0.030%, S?0.030%, balance of Fe and unavoidable impurities.

(37) The metal powder has a particle size of 15?65 ?m, a fluidity is 18 s/50 g, a sphericity is greater than or equal to 91%, and a D50 is 32 ?m.

(38) Optionally, the powder contains 160 ppm oxygen. The hollow powder rate is less than 1%.

(39) Apply the sieved powder, use ultra-high-speed laser cladding technology, and match the corresponding process to repair the surface of substrate.

(40) Optionally, the repair method is to machine the surface of substrate.

(41) Wipe the surface of mold to be repaired with acetone to remove surface grease.

(42) Carry out traditional laser cladding path planning according to a geometry of the surface of substrate, and formulating process parameters.

(43) Use optical fiber laser cladding system to clad and repair the surface of substrate, with the process parameters described in Table 3: laser power 5000 W, spot diameter 3 mm, powder feeding rate 2.4 kg/h, laser scanning rate 417 mm/s, and overlap rate 55%, the laser cladding head has an argon gas protection function, and the argon gas flow rate is 10 L/min.

(44) Using traditional laser cladding technology, when the laser scanning rate is 417 mm/s, the laser power is increased from 2250 W to 5000 W. However, it does not achieve a well-shaped cladding layer, and the powder and the substrate did not form a good metallurgical bond.

(45) The above are only preferred specific implementations of the present disclosure. The scope of protection of the present disclosure is not limited to the present disclosure. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present disclosure shall be covered by the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be subject to the scope of the protection of the claims.