超细晶45钢的制备及其组织与力学性能的研究

Study on Microstructure and Mechanical Properties of Ultrafine-Grained 45 Steel

摘要: 为了制备超细晶粒钢，将45钢淬火后进行了温轧。总变形量为50%。采用光学显微镜和透射电子显微镜研究了这一过程中的微观组织演变。原始组织是板条马氏体组织 + 少量的片状马氏体。试样在600℃~ 700℃变形后的微观结构是纳米碳化物 + 等轴超细晶铁素体，具有良好的综合力学性能，强度和塑性分别达到了646~861 MPa和21.5%~19.1%。

Abstract: In order to produce ultrafine-grained steel, 45 steel was quenched and warm-rolled. The total re-duction was 50%. The microstructural evolution during the process was studied by using an optical microscope and a transmission electron microscopy. The properties were investigated by using tensile tests. The starting microstructure was lath martensite with a small amount of flake martensite. The microstructure of the specimen compressed at 600˚C - 700˚C was nano-carbides + equiaxed ultrafine ferrite grains and a good combination of strength and ductility was obtained. The tensile strength and total elongation were 646 - 861 MPa and 21.51% - 9.1%, respectively.