(北京科技大學(xué) 材料科學(xué)與工程學(xué)院，北京100083)
摘 要: 采用Gleeble?1500型熱模擬機(jī)對(duì)電鑄Ni-W合金在變形溫度為400~600 ℃、應(yīng)變速率為0.001~0.1 s?1條件下的熱壓縮變形進(jìn)行研究，分析合金變形時(shí)的流變應(yīng)力、應(yīng)變速率及變形溫度之間的關(guān)系，研究變形溫度對(duì)合金顯微組織的影響，并得到本構(gòu)方程。結(jié)果表明：應(yīng)變速率和變形溫度對(duì)該材料的流變應(yīng)力有顯著影響，流變應(yīng)力隨變形溫度的升高而降低，隨應(yīng)變速率的提高而增大。當(dāng)變形溫度高于550 ℃時(shí)，合金流變曲線呈現(xiàn)出明顯的動(dòng)態(tài)再結(jié)晶特征，合金顯微組織為完全的動(dòng)態(tài)再結(jié)晶組織，該合金的熱變形激活能為411.55 kJ/mol。
關(guān)鍵字: 熱壓縮變形；電鑄；Ni-W合金；變形激活能；本構(gòu)方程
（School of Materials Science and Technology, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:The hot compression deformation of electroformed Ni-W alloy was studied in the temperature range of 400?600 ℃ and strain rate of 0.001?0.1 s?1 by using Gleeble?1500 thermal simulation tester. The relationships among the flow stress, the strain rate and deformation temperature were researched. The effect of deformation temperature on microstructure of the ally was investigated. The results show that the flow stress decreases with the increase of deforming temperature, while it increase with the increase of strain rate. When the deformation temperature is higher than 550 ℃, the flow curves and microstructures present apparent character of dynamic recrystallization. The hot deformation activation energy of the alloy is 411.55 kJ/mol.
Key words: hot compression deformation; electroformed; Ni-W alloy; deformation activation energy; constitutive equation
