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CN-121976186-A - Neodymium-containing high corrosion-resistant laser cladding powder for mining hydraulic cylinder and cladding method

CN121976186ACN 121976186 ACN121976186 ACN 121976186ACN-121976186-A

Abstract

The invention provides neodymium-containing high corrosion-resistant laser cladding powder for a mining hydraulic cylinder and a cladding method, wherein the neodymium-containing high corrosion-resistant laser cladding powder comprises Nd 2 O 3 powder and alloy powder, the mass percentage of the Nd 2 O 3 powder is 0.4% -1.0%, the balance is the alloy powder, and the alloy powder comprises, by mass, 19.2% -20.8% of Cr, 4.0% -8.0% of Ni, 0.3% -0.75% of Mn, 4.5% -8.5% of Mo, 0.04% -0.08% of C, 1.35% -1.52% of Si and the balance is Fe. And under inert atmosphere, carrying out laser cladding on the outer surface of the mining hydraulic cylinder by using neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder. The cladding method has the advantages of moderate hardness, good wear resistance, strong purifying capacity and low thermal cracking sensitivity on the premise of ensuring that the cladding layer has better corrosion resistance.

Inventors

  • CHENG XIANGBANG
  • FENG JUNWEI
  • ZHANG ZIQIANG
  • HAO JUNHUI
  • ZHAO XINYA
  • CUI YIFAN
  • YIN HANG
  • WANG YINGYING

Assignees

  • 郑州煤矿机械集团有限责任公司

Dates

Publication Date
20260505
Application Date
20260212

Claims (9)

  1. 1. A cladding method of neodymium-containing high corrosion resistant laser cladding powder for a mining hydraulic cylinder comprises the following steps: the neodymium-containing high corrosion resistant laser cladding powder comprises Nd 2 O 3 powder and alloy powder, wherein the mass percentage of the Nd 2 O 3 powder is 0.4-1.0%, the balance is alloy powder, and the alloy powder comprises, by mass, 19.2-20.8% of Cr, 4.0-8.0% of Ni, 0.3-0.75% of Mn, 4.5-8.5% of Mo, 0.04-0.08% of C, 1.35-1.52% of Si and the balance of Fe; Pre-treatment, namely drying and preheating the neodymium-containing high corrosion-resistant laser cladding powder at the temperature of 150-200 ℃; And cladding, namely carrying out laser cladding on the outer surface of the mining hydraulic cylinder under the conditions that the laser power is 4.5 KW-6 KW, the spot diameter is 2 mm-4 mm, the scanning speed is 7000 mm/min-9000 mm/min, the powder feeding rate is 35 g/min-55 g/min and the lap joint rate is 40% -55% by using the neodymium-containing high corrosion-resistant laser cladding powder as a raw material in an inert atmosphere, so as to obtain the neodymium-containing high corrosion-resistant laser cladding layer for the mining hydraulic cylinder.
  2. 2. The cladding method of the neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder, which is characterized by comprising, by mass, 19.2% -20.8% of Cr, 4.2% -6.5% of Ni, 0.35% -0.56% of Mn, 6.2% -7.5% of Mo, 0.04% -0.08% of C, 1.35% -1.52% of Si and the balance of Fe.
  3. 3. The cladding method of the neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder, which is characterized in that the particle size of Nd 2 O 3 powder is 40-55 μm, and the particle size of alloy powder is 60-75 μm.
  4. 4. The cladding method of neodymium-containing high corrosion resistant laser cladding powder for mining hydraulic cylinders according to claim 1, wherein the initial thickness of the neodymium-containing high corrosion resistant laser cladding layer for the mining hydraulic cylinders is 0.6 mm-1.0 mm, and the thickness of the neodymium-containing high corrosion resistant laser cladding layer for the mining hydraulic cylinders after machining is 0.3 mm-0.5 mm.
  5. 5. The method of claim 4, wherein the pre-treating step further comprises grinding and polishing the cladding area of the outer surface of the mining hydraulic cylinder, and then cleaning the cladding area with mechanical energy of acetone or absolute ethyl alcohol.
  6. 6. The neodymium-containing high corrosion-resistant laser cladding layer for the mining hydraulic cylinder is characterized by being prepared by the laser cladding method according to any one of claims 1 to 5, and the crystal phase structure of the neodymium-containing high corrosion-resistant laser cladding layer for the mining hydraulic cylinder comprises ferrite structures and austenite structures which are uniformly distributed.
  7. 7. The neodymium-containing high corrosion-resistant laser cladding layer for the mining hydraulic cylinder, which is characterized in that the hardness of the neodymium-containing high corrosion-resistant laser cladding layer for the mining hydraulic cylinder after mechanical processing is 45 HRC-52 HRC.
  8. 8. The neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder is characterized by comprising Nd 2 O 3 powder and alloy powder, wherein the mass percentage of the Nd 2 O 3 powder is 0.4% -1.0%, the balance is the alloy powder, and the alloy powder comprises, by mass, 19.2% -20.8% of Cr, 4.0% -8.0% of Ni, 0.3% -0.75% of Mn, 4.5% -8.5% of Mo, 0.04% -0.08% of C, 1.35% -1.52% of Si and the balance of Fe.
  9. 9. The neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder, which is characterized by comprising, by mass, 19.2% -20.8% of Cr, 4.2% -6.5% of Ni, 0.35% -0.56% of Mn, 6.2% -7.5% of Mo, 0.04% -0.08% of C, 1.35% -1.52% of Si and the balance of Fe.

Description

Neodymium-containing high corrosion-resistant laser cladding powder for mining hydraulic cylinder and cladding method Technical Field The invention relates to the field of laser cladding powder, in particular to neodymium-containing high corrosion-resistant laser cladding powder for a mining hydraulic cylinder and a cladding method. Background The pole column parts are exposed in the mine for a long time in the working process of the mining hydraulic cylinder, and the working environment of the mining hydraulic cylinder is often accompanied with corrosive media, and belongs to a high-chlorine and humid environment, so that the surface of the pole column parts is usually subjected to special process treatment to prolong the corrosion resistance and the service life of the hydraulic cylinder. The laser cladding technology is adopted, stainless steel cladding powder is used as a raw material, and the preparation of a cladding layer on the surface of a pole part is a common means for improving the corrosion resistance of the surface of a hydraulic jack. However, in a high-chlorine and humid mine environment, the existing stainless steel cladding powder for the oil cylinder has weak molten pool purifying capability, and MnS and pores are easy to be mixed in a cladding layer structure. Meanwhile, the structure is clad in the lap joint region, and grain boundary carbide Cr 23C6 is easy to generate at the grain boundary, so that a Cr/Mo depletion region is easy to generate in the structure, the chloride ion resistance and pitting corrosion resistance of the cladding layer are reduced, and the surface of the pole part is easy to generate punctiform corrosion and expand, so that the sealing performance of the oil cylinder is damaged. In order to solve the problem of Cr/Mo depletion region in the cladding structure of the lap joint region, the two aspects of cladding process and laser cladding powder composition can be started, the lap joint rate between cladding layers can be generally improved in the process aspect, and the dissolution of grain boundary carbide and the diffusion homogenization of alloy elements can be promoted by increasing the heat input and prolonging the high-temperature residence time. However, increasing the overlap ratio results in a larger cladding layer grain size, a lower cladding efficiency, and an increased cost. Meanwhile, heat accumulation caused by the excessively high lap joint rate can cause internal residual stress to be increased greatly, and the problems of poor surface forming quality and the like are caused. In the case of laser cladding powder compositions, however, duplex stainless steel powders with high Cr (more than 28 wt.%), high Ni (more than 16 wt%) are generally used as cladding powders. However, a higher Ni content results in an increased susceptibility to hot cracking, which leads to a need for preheating the workpiece above 300 ℃ prior to cladding, with higher cladding parameters. On the other hand, a higher Ni content also results in a stable austenite structure of the cladding layer, which is poor in hardness and wear resistance, although toughness is high. Therefore, in high chlorine, humid mine environments, how to provide the cladding layer with resistance to chloride ions and pitting corrosion has become an important point of research in the industry, wherein the effects of improving the Cr/Mo depletion region problem in the cladding structure and improving the resistance to chloride ions and pitting corrosion are obvious by changing the composition of the cladding powder. Disclosure of Invention On the premise of ensuring that the cladding layer has better corrosion resistance, the invention also has moderate hardness, good wear resistance, strong purifying capacity and low thermal crack sensitivity, on one hand, the invention changes the components of the cladding powder, and on the other hand, by adding Nd 2O3 powder, greatly reducing the Ni content in the laser cladding powder, properly reducing the Cr content and greatly improving the Mo content, refines grains, promotes the cladding layer to form a Mo-rich passivation film resisting chloride ion penetration, improves the problem of Cr/Mo depletion region in the cladding structure and improves the chlorine ion resistance and the pitting corrosion resistance, and on the other hand, reduces the defects of the cladding layer, reduces the depth of a heat affected zone, and avoids the problems of large grains, rapid increase of internal residual stress, poor surface forming quality and the like of the cladding layer by reasonably selecting the laser cladding parameters. Therefore, the technical scheme adopted by the invention is that the cladding method of the neodymium-containing high corrosion-resistant laser cladding powder for the mining hydraulic cylinder comprises the following steps: The neodymium-containing high corrosion resistant laser cladding powder comprises Nd 2O3 powder and alloy powder, wherein