中文摘要：

利用光学显微镜、洛氏硬度计和摆锤式冲击试验机对新型的高碳低合金钢ZG75Si2MnlCrB进行了低温条件下等温淬火工艺和组织力学性能的研究。结果表明，ZG75Si2MnlCrB钢经200℃等温淬火，能够获得贝氏体铁素体与奥氏体、马氏体和残留奥氏体的混合组织。该钢种理想的等温淬火工艺为920℃奥氏体化，200℃等温22h，其硬度为49．16HRC，冲击吸收能量为28J。低温等温淬火不但使组织细化，且能提高耐磨性降低生产成本。综合力学性能也有改善。

英文摘要：

The anstempering process at low temperatures, microstructure and mechanical properties of a new high carbon low alloy steel ZG75Si2MnlCrB were researched by means of optical microscopy, Rockwell hardness tester and pendulum impact testing machine. The results show that the mixed structure of bainite-ferrite with austenite, martensite and retained austenite of the steel can be obtained by austempering at 200 ℃. The ideal austempering process of the steel is austenitization at 920 ℃ and then austempering at 200 ℃ holding for 22 h, its hardness is 49. 16 HRC and the impact absorbing energy is 28 J. The austempering at low temperatures makes not only the microstructure is fined and the wear resistance is improved but also the production cost reduces, and the comprehensive mechanical properties are also improved.