(1. 重慶大學(xué) 材料科學(xué)與工程學(xué)院，重慶 400044；
2. 重慶大學(xué) 國(guó)家鎂合金材料工程技術(shù)研究中心，重慶 400044)
摘 要: 采用DEFORM-3D數(shù)值模擬軟件對(duì)超大規(guī)格的寬幅薄壁中空型材進(jìn)行結(jié)構(gòu)優(yōu)化；利用HyperXtrude數(shù)值模擬軟件對(duì)該型材的擠壓工藝進(jìn)行優(yōu)化。型材結(jié)構(gòu)優(yōu)化后，明顯改善速度分布不均勻的現(xiàn)象，規(guī)避充填不足、扭擰卷曲的問(wèn)題；確定出具有一定成形速度及最小速度均方差的優(yōu)選工藝。在此基礎(chǔ)上，成功制備出了光亮平直的超大規(guī)格寬幅薄壁中空鎂合金型材；該型材截面尺寸為502 mm×60 mm，是目前世界上規(guī)格最大的寬幅薄壁中空鎂合金型材。對(duì)型材各區(qū)域進(jìn)行顯微組織觀察和力學(xué)性能測(cè)試，各區(qū)域組織均勻細(xì)小，平均晶粒尺寸約為10~30 μm，抗拉強(qiáng)度在250 MPa以上，斷后伸長(zhǎng)率在15%以上。
關(guān)鍵字: 鎂合金；寬幅薄壁中空型材；大規(guī)格；擠壓成形；數(shù)值模擬；微觀組織；力學(xué)性能
（1. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China;
2. National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044, China）
Abstract:The structure of the wide-format thin-walled hollow profile of the large size was optimized by the DEFORM-3D numerical simulation software, and the extrusion process of the profile was optimized by HyperXtrude numerical simulation software. After the optimization of profile structure, the phenomenon of uneven velocity distribution was obviously improved, and the problem of insufficient filling and twisting curl was avoided, and a preferred process with a certain forming speed and minimum average velocity variance was determined. A bright and straight large-size wide-walled hollow magnesium alloy profile was successfully prepared, the profile cross-section size was 502 mm×60 mm, which was currently the world’s largest wide-walled thin-walled hollow magnesium alloy profile. The microstructures observation and mechanical performance testing were carried out on the regions of the profile, the regional tissues are uniform lyson, the average grain size is about 10-30 μm, the tensile strength is above 250 MPa, and the elongation is more than 15%.
Key words: magnesium alloy; wide thin-walled hollow profile; large size; extrusion; numeric simulation; microstructure; mechanical properties
