(1. 山東大學(xué) 模具工程技術(shù)研究中心，濟(jì)南 250061；
2. 山東建筑大學(xué) 材料科學(xué)與工程學(xué)院，濟(jì)南 250101)
摘 要: 通過(guò)建立鎂合金等通道轉(zhuǎn)角擠壓過(guò)程的熱力耦合有限元分析模型，對(duì)其變形過(guò)程中的溫度場(chǎng)分布進(jìn)行分析，并通過(guò)微觀組織觀察和XRD分析，獲取變形溫度對(duì)鎂合金變形行為的影響規(guī)律。結(jié)果表明：等通道擠壓過(guò)程中試件溫度分布不均勻，在模具轉(zhuǎn)角剪切部位溫度顯著升高，且存在明顯的溫度梯度。XRD分析和微觀組織觀察顯示，AZ31鎂合金變形后，錐面衍射強(qiáng)度顯著增強(qiáng)，且鎂合金的再結(jié)晶速度隨著變形溫度的升高而顯著加快。結(jié)合變形過(guò)程中溫度場(chǎng)的分布狀況，建議AZ31鎂合金等通道轉(zhuǎn)角擠壓的合理變形溫度設(shè)定為250 ℃。
關(guān)鍵字: AZ31鎂合金；等通道擠壓；有限元模擬；變形溫度
（1. Engineering Research Center for Mould and Die Technology, Shandong University, Jinan 250061, China;
2. School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China）
Abstract:A thermomechanical coupled finite element model was established and the temperature distribution of the magnesium work-piece during equal channel angular pressing (ECAP) was analysed. The effect of deformation temperature on deformation behavior of magnesium alloy was acquired by XRD analysis and microscopic examination. The results show that the distribution of temperature is not uniform during equal channel angular pressing, there exists obvious temperature gradient and the temperature increases significantly in the mold angle shear part. The XRD analysis and microscopic examination show that the pyramidal face diffraction intensity enhances significantly, the recrystallization rate of magnesium alloy increases obviously with the increase of deformation temperature. The optimal deformation temperature of 250 ℃ is obtained according to the temperature distribution.
Key words: AZ31 magnesium; equal channel angular pressing; finite element simulation; deformation temperature
