合金元素及热处理对新型槽帮钢组织与性能的影响

通过Cr、Mo等合金化设计出新型槽帮铸钢，利用扫描电镜、拉伸、冲击试验机及布氏硬度计等研究了新型槽帮钢在不同热处理条件下的组织与性能变化。结果表明，添加Cr、Mo等合金元素提高了钢的淬透性和回火稳定性，细化组织并促进碳化物析出，热处理后钢的强度、硬度、塑性和韧性得到明显改善。ZG-1试验钢经900、920℃淬火、500℃回火时抗拉强度为999～1002 MPa,屈服强度931～933 MPa,断后伸长率15.0%～14.0%,室温硬度296～298 HBW,冲击吸收能量61.0～63.0 J;ZG-2试验钢920℃淬火、500～520℃回火时强韧性更优异，抗拉强度1039～1011 MPa,屈服强度981～947 MPa,断后伸长率15.0%～15.3%,室温硬度305～298 HBW,冲击吸收能量64.5～67.5 J,可以满足刮板输送机中部槽材料的性能要求。

Effects of alloy element and heat treatment on microstructure and properties of new-type slot edge steel

A new-type slot edge steel was designed by alloying with Cr, Mo, etc. The microstructure and properties of the new-type slot edge steel under different heat treatment processes were studied by means of scanning electron microscope, tensile and impact tester and Brinell hardness tester. The results show that the addition of Cr and Mo alloying elements improves the hardenability and tempering stability of the tested steel, refines the microstructure and promotes the precipitation of carbides. The strength, hardness, plasticity and toughness of the tested steel are significantly improved after proper heat treatment. The ZG-1 tested steel obtains tensile strength of 999-1002 MPa, yield strength of 931-933 MPa, elongation of 15.0%-14.0%, room temperature hardness of 296-298 HBW, impact absorbed energy of 61.0-63.0 J after water quenching at 900 ℃ or 920 ℃ and tempering at 500 ℃. Moreover, the combination of strength and toughness for the ZG-2 tested steel processed by water quenching at 920 ℃ and tempering at 500 ℃ or 520 ℃ is more excellent, with the tensile strength of 1039-1011 MPa, the yield strength of 981-947 MPa, the elongation after fracture of 15.0%-15.3%, the room temperature hardness of 305-298 HBW, and the impact absorbed energy of 64.5-67.5 J, which meet the properties requirements of the material for the middle slot of the scraper conveyor.