40Cr钢表面纳米化的研究

Research on Surface Nanocrystallization of 40Cr Steel

采用超音速微粒轰击技术(SFPB)对40Cr调质钢进行表面纳米晶结构制备,并利用TEM、XRD、GX-71型金相显微镜和TUKON2100显微/维氏硬度计等对表面纳米层的组织结构和显微硬度进行了分析研究。结果表明,经过SFPB表面处理后,在40Cr调质钢表面晶粒细化,形成了随机取向的铁素体和渗碳体纳米晶粒,晶粒尺寸达到10 nm,纳米层厚度为40μm;纳米晶粒尺寸随着距表面距离增加而增大,纳米化主要是位错运动的结果;经SFPB处理后表层的显微硬度提高到526HV,且随着深度的增加硬度迅速降低。

By means of Supersonic Fine Particles Bombarding （ SFPB）, nanostructured surface layer was fabricated on 40Cr steel plate. The organic structure and micro-hardness of the nanostructured surface layer are studied and analyzed by means of TEM, XRD, GX-71 type of metal-phase microscope and TUKON2100 microscope/vicker＇ s hardometer. The results indicate that after SFPB surface treatment, the nanocrystal grains of ferrite and cementite phases with random direction are formed on 40Cr steel surface crystal grain fineness with the size of crystal grain reaching 10 nm, and the thickness of nanolayer being 40 μm. The nanograin size increases with an increase in surfaee distance, and the grain refinement is mainly due to the dislocation movement. After the SFPB treatment, the surface mierohardness can increase to 526HV, but hardness is fast reduced with an increase in the depth.