(1. 福州大學(xué) 材料科學(xué)與工程學(xué)院,福州 350116; 2. 莆田學(xué)院 機電工程學(xué)院,莆田 351100; 3. 福建工程學(xué)院 材料科學(xué)與工程學(xué)院,福州 350118; 4. 福建工程學(xué)院 福建省新材料制備與成形技術(shù)重點實驗室,福州 350118)
摘 要: 采用電子背散射衍射技術(shù),研究室溫下CoCrFeMnNi高熵合金在準靜態(tài)單向拉伸(應(yīng)變速率為1×10-1 s-1)過程中顯微組織的演變。結(jié)果表明:合金的變形機制主要是位錯的滑移,同時伴隨著少量的孿生。當(dāng)應(yīng)變約為0.81%時,合金開始出現(xiàn)新的Σ3孿晶界。晶向á001?附近的拉伸軸向á001?方向轉(zhuǎn)動,形成弱的á001?//RD絲織構(gòu),符合Toylor模型,晶粒拉伸軸向á001?-á111?連線轉(zhuǎn)動,符合Sachs模型。晶粒尺寸顯著影響晶粒的轉(zhuǎn)動速率,小尺寸晶粒轉(zhuǎn)動最快,大尺寸晶粒次之,中等尺寸晶粒轉(zhuǎn)動最慢。晶粒Schmid因子越大,晶粒的轉(zhuǎn)動越快。
關(guān)鍵字: 高熵合金;背散射電子衍射;微觀組織;準靜態(tài)拉伸;晶粒轉(zhuǎn)動
(1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350116, China; 2.School of Mechanical and Electrical Engineering, Putian University, Putian 351100, China; 3. College of Materials Science and Engineering, Fujian University of Technology, Fuzhou 350118, China; 4. Fujian Provincial Key Laboratory of Advanced Materials Processing and Application, Fujian University of Technology, Fuzhou 350118, China)
Abstract:The evolution of microstructure of CoCrFeMnNi high-entropy alloy during quasi-static tensile (strain rate 1×10-1 s-1) were investigated using electron backscatter diffraction technology. The results show that the dominant deformation mechanism is dislocation gliding, which is accompanied with less twinning. The alloy generates new Σ3 twin boundaries when the strains is 0.81%. The tensile axes close to á001? rotate toward á001? and form a weak á001?//RD fiber texture following Toylor model. The tensile axes rotate to the line of á001?-á111? following Sachs model, the grain size influences the rotational speed of grains. The rotational speed of small grain is the fastest than big grains and medium grains, and the medium grain is the slowest than other grains. The bigger Schmid factor of grain is, the faster grain rotation is.
Key words: high-entropy alloy; electron backscatter diffraction technology; microstructure; quasi-static tensile; grain rotation


