(西北工業(yè)大學(xué) 材料學(xué)院，西安 710072)
摘 要: 采用熱模擬壓縮試驗(yàn)研究GH696合金在變形溫度為880~1020 ℃、應(yīng)變速率為0.01~10.0 s-1、變形程度為30%~60%條件下的高溫變形行為。采用金相顯微鏡對(duì)GH696合金高溫壓縮變形后的顯微組織進(jìn)行觀察。結(jié)果表明：較高的變形溫度和較低的應(yīng)變速率有利于GH696合金的動(dòng)態(tài)再結(jié)晶。采用加工硬化率-流動(dòng)應(yīng)力曲線確定GH696合金的動(dòng)態(tài)再結(jié)晶臨界應(yīng)變，應(yīng)用Avrami方程建立GH696合金的動(dòng)態(tài)再結(jié)晶體積分?jǐn)?shù)模型，并根據(jù)合金的金相定量試驗(yàn)結(jié)果建立GH696合金的動(dòng)態(tài)再結(jié)晶晶粒尺寸模型。
關(guān)鍵字: GH696合金；熱模擬壓縮；動(dòng)態(tài)再結(jié)晶；晶粒尺寸
（School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract:The deformation behavior of GH696 superalloy was studied by isothermal compression experiments the deformation temperatures ranging from 880 to 1120 ℃, strain rates ranging from 0.01 to 10.0 s-1 and deformation degree ranging from 30% to 60%. The microstructure of GH696 superalloy after compression was observed on a microscope. The results show that dynamic recrystallization of GH696 superalloy occurs more easily at higher deformation temperature and lower strain rate. The critical strain of dynamic recrystallization of this alloy is identified based on the work hardening rate versus flow stress curves. The kinetics of dynamic recrystallization of GH696 superalloy is established based on Avrami equation. A model for DRX grain size is established based on OM experimental measurement results of GH696 superalloy.
Key words: GH696 superalloy; isothermal compression; dynamic recrystallization; grain size
