硅对中碳低合金贝氏体/马氏体复相耐磨钢的影响

研究了不同含量的硅元素和热处理工艺对中碳低合金钢的组织与性能的影响.在中碳钢中,加入少量的硅、锰、铬合金元素,采用中频感应炉进行熔炼,砂型浇注.炉料由废钢、生铁、硅铁、锰铁、铬铁组成,浇注出的试样用箱式电阻炉加热到910℃,保温2h,于硝盐槽中进行等温淬火,分别为280℃保温1.5h,2h和2.5h.对热处理后的试样和铸态下的原始试样进行洛氏硬度和冲击韧性试验,对比发现,经过热处理后的试样硬度和冲击韧性性能均有明显提高,采用金相显微镜对试样进行组织观察,发现热处理后的试样得到贝氏体与马氏体组织.试验表明：贝氏体与马氏体复相可以有效提高硬度和冲击韧性,冲击韧性最高为27.623J/mm^2,洛氏硬度最高达到57.25.

Effect of Si on the Wear Resisting Steel of Medium Carbon Low Alloy with B/M Composite Phase

The influence of different silicon contents on the medium carbon low-alloy steel microstructure and mechanical properties was studied under different heat treatment processes.Medium carbon steel was smelt in a medium frequency induction furnace and into some silicon,manganese and chromium alloys were added.Samples were cast in sand mold.The charge was made up of scrap steel,ferrosilicon,ferromanganese,ferrochrome and pig iron.At 910℃ for 2 h in the box-type electrical resistance furnace,the heated samples were put into the niter salt bath at 280℃ for 1.5,2.0 and 2.5 h respectively.Compared isothermal quenching samples with the as cast ones,hardness and tensile strength was distinctly improved.Bainite and martensite in the matrix was observed by the metallographic microscope.The results showed that bainite and martensite composite phase can promote the hardness,the tensile strength can be as high as 27.623J/mm^2,and the hardness is HRC57.25.