激光增材含铝马氏体不锈钢的高温摩擦磨损性能研究

Study on High-Temperature Friction and Wear Characteristics of Aluminum-Containing Martenitic Stainless Steel Sample of Laser Additive

激光增材马氏体不锈钢可应用于600℃以下的高温部件,为了进一步提高其高温耐磨性能,制备了4种不同铝含量(0、1%、2%、3%,质量分数)的马氏体不锈钢试样,采用箱式电阻炉对4种马氏体不锈钢试样分别在25、200、400、600℃温度下进行热处理。采用OM、XRD、SEM、3D景深显微镜、高温摩擦磨损试验机等仪器和JMatPro软件研究了试样的金相组织与高温摩擦磨损性能。结果表明:随着铝含量的增加,试样的平均硬度从57.87 HRC降至42.46 HRC,随着600℃保温时间的延长,试样的硬度均快速下降并趋于稳定,其值从44.79 HRC降至28.70 HRC,铝含量的增加对试样在25℃下的摩擦系数的影响并不明显,其值均在0.8~0.9之间;当铝含量达到3%时,试样在600℃环境中的摩擦系数降至0.45左右,约为25℃下的52.94%,体积磨损量降至0.0214 mm^(3),约为25℃下的9%,试样主相为马氏体相及少量碳化物等析出相。添加3%铝可显著改善激光增材马氏体不锈钢的高温摩擦磨损性能。

Laser additive martensite stainless steel can be applied to high temperature parts below 600 ℃. In order to further improve its high temperature wear resistance, four kinds of martensite stainless steel samples with different aluminum content(0,1%, 2% and 3%, mass fraction) were prepared. The four types of martensitic stainless steel samples were heat treated at temperatures of 25, 200, 400, and 600 ℃ using a box type resistance furnace. Moreover, the metallographic structure and high-temperature friction and wear properties of the samples were studied by OM, XRD, SEM, 3D depth-of-field microscope, high-temperature friction and wear testing machine and JMatPro software. Results showed that with the increase of the aluminum content, the average hardness of the specimen decreased from 57.87 HRC to 42.46 HRC. With the extension of the insulation time at 600 ℃, the hardness of the samples decreased rapidly and stabilized, and its value decreased from 44.79 HRC to 28.70 HRC. In addition, the increase in aluminum content had no obvious effect on the friction coefficient of the sample at 25 ℃, and its values were in the range of 0.8~0.9. When the aluminum content reached 3%, the friction coefficient of the sample in 600 ℃ environment was reduced to about 0.45, which was about 52.94% of that at 25 ℃. The volume wear amount declined to 0.021 4 mm^(3), which was approximately 9% of that at 25 ℃. Meanwhile, the main phase of the sample was composed of martensite and a small amount of precipitated phases such as carbide. In general, the addition of 3% aluminum could significantly improve the high-temperature friction wear performance of martensite stainless steel prepared by laser additive.