(1. 華中科技大學(xué) 材料科學(xué)與工程學(xué)院 材料成形與模具技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室，武漢 430074；
2. 深圳市萬澤中南研究院有限公司，深圳 518000；
3. 中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083；
4. 深圳市萬澤航空科技有限責(zé)任公司，深圳 518000)
摘 要: 采用有限元模擬和實(shí)驗(yàn)驗(yàn)證的方法研究一種新型鎳基粉末高溫合金包覆擠壓過程中工藝參數(shù)的影響規(guī)律，并對(duì)工藝窗口進(jìn)行優(yōu)化。結(jié)果表明，擠壓速度和坯料初始溫度對(duì)應(yīng)變的影響不顯著，擠壓比與擠壓變形程度呈線性相關(guān)，擠壓比的增加和模角的減小可以提高擠壓棒材沿徑向應(yīng)變分布的均勻性。擠壓速度和坯料初始溫度的增加、擠壓比和模角的減小可以提高擠壓棒材溫度分布的均勻性。基于組織控制準(zhǔn)則，對(duì)工藝窗口進(jìn)行優(yōu)化并進(jìn)行工藝實(shí)驗(yàn)。擠壓后的高溫合金無宏觀開裂，析出相均勻分布，晶粒尺寸細(xì)小，驗(yàn)證了工藝優(yōu)化的可行性。
關(guān)鍵字: 鎳基粉末高溫合金；包覆擠壓；數(shù)值模擬；晶粒尺寸；工藝窗口優(yōu)化
（1. State Key Laboratory of Materials Processing and Die and Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;
2. Shenzhen Wedge Central South Research Institute Co., Ltd., Shenzhen 518000, China;
3. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
4. Shenzhen Wedge Aviation Technology Co., Ltd., Shenzhen 518000, China）
Abstract:The influence of processing parameters on the extrusion process of hot isostatic pressed nickel-based powder superalloy was studied by means of finite element simulation and experimental verification. The process window was optimized. The results show that the effect of extrusion speed and initial temperature on strain is not significant, the extrusion ratio is linearly correlated with the degree of extrusion deformation. The increase of extrusion ratio and the decrease of die angle can improve the uniformity of the radial distribution of the extruded bar. The uniformity of temperature distribution can be improved with the increase of extrusion velocity and initial temperature of billet and the decrease of extrusion ratio and die angle. Based on the microstructure control criterion, the process window was optimized. Then, the extruded bar with uniform fine grain and without defects is obtained by experiment. This study verifies the feasibility of the optimum design of parameters in the engineering practice of nickel-base powder superalloy cladding extrusion.
Key words: nickel-based powder superalloy; cladding extrusion; numerical simulation; grain size; process window optimization
