發(fā)布時(shí)間：2019-01-04 18:35

【摘要】：采用等通道轉(zhuǎn)角擠壓(equal channel angular pressing,ECAP)方法成功擠壓了Mg-3Sn-0.5Mn合金,采用OM和TEM觀察了ECAP過程中合金微觀組織和晶粒尺寸的變化,測(cè)試了ECAP后Mg-3Sn-0.5Mn合金的力學(xué)性能與腐蝕性能,通過XRD觀察了ECAP變形后的織構(gòu)取向變化。結(jié)果顯示,ECAP后得到了超細(xì)晶Mg-3Sn-0.5Mn合金組織,在320℃下經(jīng)過4道次擠壓后平均晶粒尺寸細(xì)化到了1.65 mm,局部晶粒細(xì)化到了0.80 mm,晶粒細(xì)化是劇烈塑性變形與再結(jié)晶共同作用的結(jié)果。4道次變形后,延伸率從22.2%上升到58.6%,抗拉強(qiáng)度從242.8 MPa下降到195.6 MPa,延伸率提高了約3倍,強(qiáng)度略有下降。ECAP后的Mg-3Sn-0.5Mn合金織構(gòu)擇優(yōu)取向發(fā)生了顯著改變,這種變化有利于滑移系的開動(dòng),提高了材料的塑性,但對(duì)強(qiáng)度有一定的不利影響。ECAP后的Mg-3Sn-0.5Mn合金力學(xué)性能受到改變的織構(gòu)擇優(yōu)取向和細(xì)晶強(qiáng)化的共同影響。
[Abstract]:The Mg-3Sn-0.5Mn alloy was extruded successfully by equal channel angular extrusion (equal channel angular pressing,ECAP) method. The changes of microstructure and grain size of the alloy during the ECAP process were observed by OM and TEM. The mechanical and corrosion properties of Mg-3Sn-0.5Mn alloy after ECAP were tested. The texture orientation of ECAP was observed by XRD. The results showed that the microstructure of ultrafine grained Mg-3Sn-0.5Mn alloy was obtained after ECAP, and the average grain size was refined to 1. 65 mm, local grain size to 0. 80 mm, after 4 passes extrusion at 320 鈩，

本文編號(hào)：2400644