(1. 燕山大學(xué) 機(jī)械工程學(xué)院，秦皇島 066004； 2. 中南大學(xué) 高性能復(fù)雜制造國家重點(diǎn)實(shí)驗(yàn)室，長沙 410083； 3. 南京迪威爾高端制造股份有限公司，南京 210048； 4. 燕山大學(xué) 亞穩(wěn)材料制備技術(shù)與科學(xué)國家重點(diǎn)實(shí)驗(yàn)室，秦皇島 066004)
摘 要: 采用低速等溫模鍛工藝制備7A85鋁合金航空接頭鍛件，并對其在低速等溫條件下塑性變形的微觀機(jī)理進(jìn)行分析。結(jié)果表明：低速等溫模鍛工藝有利于航空接頭鍛件的塑性成形，鍛件成形質(zhì)量良好，且鍛件內(nèi)部顯微組織細(xì)小均勻。在低速等溫變形條件下，晶界滑移是航空接頭鍛件塑性變形的主要機(jī)制，而擴(kuò)散蠕變是晶界滑移的主要因素。基于空位擴(kuò)散理論，建立7A85鋁合金航空接頭鍛件在極低變形速度條件下的塑性變形本構(gòu)方程，為低速等溫鍛造工藝提供理論指導(dǎo)。
關(guān)鍵字: 航空接頭鍛件；低速等溫模鍛；晶界滑移；微觀機(jī)理
（1. College of Mechanical Engineering, Yanshan university, Qinhuangdao 066004, China; 2. State Key Laboratory of High Perfermance Complex Manufacturing, Central South University, Changsha 410083, China; 3. Nanjing Develop Advanced Manufacturing Co., Ltd., Nanjing 210048, China; 4. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China）
Abstract:The aviation forging of 7A85 aluminum alloy was prepared by the isothermal forging process with low speed, and the microcosmic mechanism of the plastic deformation was analyzed. The results show that the aviation forging is easily formed by using isothermal forging process with low speed, and the uniform microstructure is obtained. Grain boundary sliding is the main mechanism during the isothermal forging process with a low speed, and the diffusion creep is the main factor leading to the grain boundary sliding. Therefore, based on the vacancy diffusion theory, the plastic deformation constitutive equation of aviation forging under extremely low speed isothermal forging process is established in order to provide guidance for the low speed isothermal forging process.
Key words: aviation joint forging; low speed isothermal forging process; grain boundary sliding; microcosmic mechanism
