(1．中南林業(yè)科技大學(xué) 機(jī)電工程學(xué)院，長(zhǎng)沙 410004；
2．中南大學(xué) 粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 以經(jīng)DP工藝處理的GH4169合金為對(duì)象，研究熱加工高通量雙圓錐臺(tái)試樣測(cè)試方法，利用數(shù)值模擬方法進(jìn)行雙圓錐臺(tái)試樣關(guān)鍵尺寸設(shè)計(jì)，探討熱加工工藝參數(shù)對(duì)雙圓錐臺(tái)試樣等效應(yīng)變場(chǎng)分布的影響規(guī)律，進(jìn)行實(shí)際試驗(yàn)驗(yàn)證，分析晶界取向差和晶界分布特征。結(jié)果表明:摩擦因數(shù)對(duì)等效應(yīng)變影響顯著，隨著摩擦因數(shù)的提高，試樣中心位置應(yīng)變量增加，應(yīng)變梯度加大；隨著變形溫度的升高和變形速率的減小，試樣中心附近的等效應(yīng)變降低，能促進(jìn)δ相的溶解和斷裂，加快動(dòng)態(tài)再結(jié)晶的發(fā)生，增大動(dòng)態(tài)再結(jié)晶晶粒尺寸；經(jīng)(1000 ℃，0.01 s-1)熱變形后高通量雙圓錐臺(tái)試樣中心由于動(dòng)態(tài)再結(jié)晶導(dǎo)致小角晶界數(shù)量很少，統(tǒng)計(jì)頻率僅為5.6%，外緣變形量低，晶界數(shù)量中大角晶界占比高達(dá)92.3%，晶內(nèi)分布有原始孿晶；隨著變形溫度提高，小角晶界不斷減少，孿晶數(shù)量有所增加。
關(guān)鍵字: GH4169合金；熱加工；高通量測(cè)試；數(shù)值模擬
（1. College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology,
Changsha 410004, China;
2. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:High throughput testing technology for the hot working of superalloy was put forward for GH4169 alloy with delta process. The key dimension of the double cone sample was designed by finite element modeling method. The effects of hot working parameters on the effective strain were discussed. Then experiments were carried out, grain boundary orientation and grain boundary distribution character were researched. The results show that effect of friction coefficient on the effective strain is significantly. With increasing the friction coefficient, the strain of specimen center and the strain gradient increase. With increasing deformation temperature and decreasing strain rate, the effective strain of specimen center reduces. It can promote the dissolution and breakage of δ phase. Then the dynamic recrystallization volume fraction and dynamic recrystallization grain size are raised. When the hot working parameter is (1000 ℃, 0.01 s-1), the number of low angle grain boundaries is 5.6% at the center of double cone sample. The ratio of high angle grain boundaries is 92.3%, and twin crystals mainly distribute at the outer rim due to the lowest strain. With increasing deformation temperature, the number of low angle grain boundaries decrease, the grain size and twin increase.
Key words: GH4169 alloy; hot working; high-throughput testing technology; numerical simulation
