边界润滑条件下18Cr2Ni4WA钢的摩擦诱发马氏体相变及其耐磨特性的研究

Friction Induced Martensite Transformation and Wear Resistance of 18Cr2Ni4WA Steel Under Boundary Lubrication

用18Cr2Ni4WA钢,经渗碳、淬火和冷处理,以获得不同残留奥氏体含量的试样,进行了与T10钢金属盘对磨的边界润滑磨损试验研究。结果表明,磨损过程中确实存在摩擦诱发马氏体相变,且碳含量低的残留奥氏体较碳含量高的残留奥氏体更易发生诱发相变;摩擦诱发马氏体对提高材料的耐磨性是有利的,而残留奥氏体对耐磨性的影响却存在一个临界应力σc;当外加应力>σc时,残留奥氏体对提高材料的耐磨性有利;当外加应力<σc时,残留奥氏体对提高材料的耐磨性不利,并且当残留奥氏体和外加应力搭配适当时,耐磨性可达最高值。

Different retained austenite contents were obtained in the 18Cr2NiWA steel carburized and quenched by subzero treating at different temperatures. The specimens were tested under boundary lubricated sliding wear against T10 steel plat by the pin on disk method. The results show that friction induced martensite do exist in the course of wear, and the retained austenite with lower carbon content is easier to transform to martensite than that with higher carbon. Friction induced martensite is always benefit to improving the wear resistance ,but there exists a threshold stress value trc for retained austenite affecting the wear resistance. When the stress is greater than trc ,the retained austenite is benefit to improving the wear resistance, otherwise it will impair the wear resistance. The wear resistance will reach a maximum when the retained austenite content fits with the external stress.