深冷处理对高速钢膨胀曲线及摩擦磨损性能的影响

Effect of Deep Cryogenic Treatment on Dilatometric Curve and Tribological Properties of High Speed Steel

越来越多的科技论文提到,经过传统热处理的高速钢采用深冷处理可进一步提高其性能。本文着重探讨PM S390 MC高速钢试样经深冷处理后性能的改善,研究了深冷处理对该高速钢回火过程中的膨胀曲线及其抗磨料磨损和抗冲蚀磨损性能的影响,并与仅经常规热处理即淬火和三次高温回火的同种钢进行了对比研究。膨胀试验证明,回火时发生的常见过程取决于钢的初始状态(仅淬火或淬火后深冷处理)。这些测试结果表明,深冷处理并不能完全消除残留奥氏体,尤其是在采用高奥氏体化温度时。摩擦试验结果证明,深冷处理工艺可以显著改善高速钢的抗冲蚀磨损性能,而抗磨料磨损性能则取决于钢的奥氏体化温度。

Advantages of deep cryogenic treatment （DCT） over the standard heat treatment of high speed steels for the purpose of obtaining better properties are quoted in an increasing number of scientific papers to be found in literature. This paper deals with the improvements in high speed steel properties achieved by using DCT on test samples made of PM S390 MC high speed steel. The effect of DCT on the dilatometric curve during tempering and on the abrasive and the erosion wear resistance has been investigated and compared with results obtained from a set of test samples made of the same steel heat treated by the conventional method （ hardened and three times high temperature tempered ）. Dilatometric tests confirmed the existence of common processes in tempering, which depend on the initial state of steel （only quenched, and quenched and deep cryogenically treated）. These tests showed that the DCT had not completely eliminated the residual austenite, particularly in the case of the highest austenisation temperature. The tribological results obtained confirm that the application of DCT results in significantly improved erosive wear resistance, while the abrasive wear resistance depends on the temperature of austenisation used.