(北京有色金屬研究總院 有色金屬材料制備加工國家重點(diǎn)實(shí)驗(yàn)室，北京 100088)
摘 要: 在變形溫度為250~400 ℃，應(yīng)變速率為0.002~1 s−1時(shí)，在Gleeble−1500D熱模擬試驗(yàn)機(jī)上對(duì)不同狀態(tài)(鑄態(tài)、(410 ℃，4 h)、(410 ℃，16 h))的AZ80鎂合金進(jìn)行熱壓縮變形行為研究；根據(jù)實(shí)驗(yàn)結(jié)果建立熱加工圖，并利用熱加工圖分析均勻化程度對(duì)合金再結(jié)晶能力的影響。結(jié)果表明：隨著均勻化程度的提高，相同條件下的峰值應(yīng)力隨之提高，發(fā)生動(dòng)態(tài)再結(jié)晶的溫度和應(yīng)變速率逐漸提高；410 ℃、16 h處理合金的再結(jié)晶能力明顯強(qiáng)于其他2種狀態(tài)合金的，在(400 ℃、0.01 s−1)時(shí)動(dòng)態(tài)再結(jié)晶晶粒更加均勻、細(xì)小，晶間無條帶狀共晶組織；對(duì)AZ80鎂合金在大變形之前進(jìn)行完全均勻化處理有利于動(dòng)態(tài)再結(jié)晶組織的控制，其最佳變形溫度范圍為380~400 ℃，變形速率范圍為0.002~0.1 s−1。
關(guān)鍵字: AZ80鎂合金；均勻化處理；熱壓縮；熱加工圖；顯微組織
AZ80 magnesium alloys with processing map
（State Key Laboratory for Fabrication and Processing of Nonferrous Metals,
Beijing General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The hot deformation behaviors of AZ80 magnesium alloys at different states (as-cast, (410 ℃, 4 h) (410 ℃, 16 h)) in the temperature range of 250−400 ℃ and strain rate range of 0.002−1 s−1 were investigated by hot compression test on a Gleeble−1500D simulator. Based on these data, three processing maps were developed to assist in the analysis of the influence of homogenization on the deformation properties of AZ80 alloys. The results show that, with increasing the degree of uniformity, the peak stresses are enhanced at the same temperature and strain rate, the strain rate and temperature of the dynamic recrystallization are gradually raised, and the recrystallization ability of the alloy after homogenization at 410 ℃ for 16 h is the best among three alloys; the grains of alloys are more even and more finer after deformation under the condition of 400 ℃ and 0.01 s−1, without visible branded eutectic structure in the intergranular. Therefore, complete homogenization before large deformation for AZ80 Mg-alloys is in favor of the microstructure control of dynamic recrystallization, and the optimum ranges of deformation temperatures and rates are 380−400 ℃ and 0.002−0.1 s−1, respectively.
Key words: AZ80 magnesium alloy; homogenization; hot compression; processing map; microstructures
