New forming method of manufacturing cylindrical parts with nano/ultrafine grained structures by power spinning based on small plastic strains  

作　　者：XIAO GangFeng XIA QinXiang CHENG XiuQua LONG Hu 

机构地区：[1]School of Mechanical and Automotive Engineering, South China University of Technology [2]Department of Aircraft Maintenance Engineering, Guangzhou Civil Aviation College [3]Department of Mechanical Engineering, The University of Sheffield

出　　处：《Science China(Technological Sciences)》2016年第11期1656-1665,共10页中国科学（技术科学英文版）

基　　金：supported by National Natural Science Foundation of China(Grant No.51075153);Natural Science Foundation of Guangdong Province(Grant No.10151040301000000);Key Laboratory of Precision Equipment and Manufacturing Technology of Guangdong Province(Grant No.PEMT1202);the EU FP7 Marie Curie International Research Staff Exchange Scheme(IRSES)Mat Pro Future Project(Grant No.318968)

摘　　要：A new spinning method to manufacture the cylindrical parts with nano/ultrafine grained structures is proposed, which consists of quenching, power spinning and recrystallization annealing. The microstructural evolution during the different process stages and macroforming quality of the spun parts made of ASTM 1020 steel are investigated. The results show that the microstructures of the ferrites and pearlites in the ASTM 1020 steel are transformed to the lath martensites after quenching. The martensite laths obtained by quenching are refined to 87 nm and a small amount of nanoscale deformation twins with an average thickness of 20 nm is generated after performing a 3-pass stagger spinning with 55% thinning ratio of wall thickness, where the equivalent strain required is only 0.92. The equiaxial ferritic grains with an average size of 160 nm and nano-carbides are generated by subsequent recrystallization annealing at 480°C for 30 min. The spun parts with high dimensional precision and low surface roughness are obtained by the forming method developed in this work, combining quenching with 3-pass stagger spinning and recrystallization annealing.

关 键 词：nano/ultrafine grained structure cylindrical parts QUENCHING power spinning recrystallization annealing small plastic strain 

分 类 号：TG306[金属学及工艺—金属压力加工] TG161