【摘要】 研究了等径弯曲通道(ECAP)变形后45钢中先共析铁素体及珠光体组织的演变特征。结果表明,ECAP变形4道次后,片层状的珠光体组织演变成了超细的渗碳体颗粒均匀分布于亚微晶铁素体基体的组织。先共析铁素体由原始的平均晶粒尺寸约为30μm演变为大角度晶界分离的、平均晶粒尺寸约为0.4μm的超细晶组织。ECAP变形后,先共析铁素体首先在其内部会形成具有薄片层界面(LBs)的板条位错胞甚至亚晶组织。进一步变形时位错胞或亚晶可继续细化。再进一步变形时通过晶界滑移和晶粒旋转的方式可以获得具有大角度晶界分离的、等轴的超细晶组织。更多还原

【Abstract】 The microstructure evolution of proeutectoid ferrite and pearlite in No.45 Steel after ECAP(equal-channel angular pressing) was investigated.The results show that the microstructure of lamellae pearlite has changes to(ultra-fine) cementite particles throughout the ferrite matrix uniformly after four-pass distortion.The proeutectoid ferrite grains of about 30 μm change to high-angle boundary ultra-fine grains of about 0.4 μm.After ECAP distortion,even dislocations and subgrains with lamellar boundaries(LBs) are formed in inner proeutectoid ferrite grains.With further deformation,the dislocations and subgrains are refined.At the larger strain,equiaxed ultra-fined ferrite grains with high-angle boundaries are formed by grains sliding and rotation.更多还原