(1. 安徽工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院,馬鞍山 243002;
2. 中國人民解放軍海軍工程大學(xué) 化學(xué)與材料系,武漢 430033;
3. 馬鞍山鋼鐵股份有限公司 第四鋼軋總廠,馬鞍山 243000)
摘 要: 在應(yīng)變速率為1×10-3~1 s-1、溫度為300~450 ℃條件下,采用Gleeble-3500型熱模擬機(jī)對(duì)Mg-1.3Zn-1.7Ca (質(zhì)量分?jǐn)?shù),%)鎂合金(ZX115)進(jìn)行單軸熱壓縮實(shí)驗(yàn);通過分析ZX115鎂合金的真應(yīng)力-真應(yīng)變曲線,探討變形溫度和應(yīng)變速率對(duì)其流變曲線中峰值應(yīng)力、峰值應(yīng)變及Zener-Hollomom參數(shù)的影響,建立描述該合金高溫壓縮變形的本構(gòu)方程。將本構(gòu)方程應(yīng)用于有限元分析軟件 DEFORM 3D中,并對(duì)ZX115鎂合金熱壓縮過程進(jìn)行數(shù)值模擬,利用后處理程序,分析工件內(nèi)部的應(yīng)變速率場、應(yīng)變場和溫度場變化。研究表明:溫度越高或應(yīng)變速率越低時(shí),流變曲線所達(dá)到的峰值應(yīng)力越小,而在相同的應(yīng)變速率下,峰值應(yīng)變也隨著變形溫度的升高而明顯減小;ZX115合金熱壓縮過程具有明顯的變形不均勻性,為了合理控制變形后的再結(jié)晶晶粒尺寸,可適當(dāng)降低形變溫度和應(yīng)變速率。
關(guān)鍵字: ZX115鎂合金;Ca;熱壓縮;流變曲線;本構(gòu)方程
(1. School of Materials Science and Engineering, Anhui University of Technology, Maanshan 243002, China;
2. Department of Chemistry and Materials, Naval University of Engineering, PLA, Wuhan 430033, China;
3. No. 4 Steel Making and Rolling General, Maanshan Iron and Steel Co., Ltd., Maanshan 243000, China)
Abstract:The hot compressions of Mg-1.3Zn-1.7Ca (mass fraction, %)magnesium alloy (ZX115) were carried out on Gleeble-3500 thermal simulator at a strain rate of 1×10-3-1 s-1 and temperature range of 300-450 ℃. Based on the true stress-strain curves of ZX115 magnesium alloy obtained from experiments, the effects of deformation temperatures and strain rates on the peak stress, peak strain and Zener-Hollomon parameter were discussed, and the constitutive equations were established to describe the hot compression of ZX115 magnesium alloy. These constitutive equations were applied into finite element analysis software DEFORM 3D and then the hot compressions of ZX115 magnesium alloy were simulated. The variation and distribution of strain rate, strain and temperature in the compressed workpiece were analyzed by the post-processing procedures. The results show that peak stress decreases with increasing the deformation temperature or decreasing the strain rate, and the peak strain decreases with increasing the temperature under a given strain rate. The hot compressions of ZX115 magnesium alloy exhibits a nonuniform characteristic. In order to control the recrystallized grain size, the deformation temperature and strain rate should be necessarily decreased.
Key words: ZX115 magnesium alloy; Ca; hot compression; flow curve; constitutive equation


