采用透射电镜对C194铜合金连续挤压过程中的典型变形区粘着区、直角弯曲前变形区、直角弯曲后变形区、扩展成形区组织进行取样分析研究.结果表明,在粘着区,未发生第二相析出,仅出现了形变所致的晶粒拉伸以及少量位错缠结;在直角弯曲前变形区,晶界处出现少量尺寸在30 nm左右的圆形或椭圆形第二相析出颗粒,析出物为Fe3P化合物,在一些区域位错缠结发展成位错胞;在直角弯曲后变形区,晶粒内部出现了数量较多且分布弥散均匀的第二相颗粒,尺寸在3～5 nm左右,同时,在前变形区出现主要分布在晶界位置的较大尺寸第二相析出颗粒的数量也出现上升,且尺寸有所增长,平均可达45～50 nm左右;在扩展成形区,此区域内析出较小颗粒的数量明显增多,呈弥散状态分布在晶粒中,同时尺寸较前变形区有所增长,达到约10～15 nm左右.%The microstructures in typical deformation zones such as adhesion,before and after 90°bending,extended forming region during continuous extrusion of C194 copper alloy were studied by sampling and analysis with TEM.The results indicate that in the adhesion area,second phase precipitation do not occur,but deformation induces grain tension and a small amount of dislocation.In before 90°bending zone,a small size of about 30nm second phase precipitates in the round or oval shape appear at grain boundaries,which are Fe3 P compounds.In some areas of dislocation,tangles develop into dislocation cell.In after 90°bending zone,a large num ber of second phase particles uniformly disperse in the grain with the sizes about 3-5 nm.At the same time,the number of second phase particles with larger sizes in the grain boundary of former deformation has also increased,and their sizes become larger,with an average of 45-50 nm.In the expansion forming zone,the number of small precipitates,which diffuse in the grains increases significantly.At the same time,compared with the former deformation zone,the size has increased,reaching about 10-15nm.
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