(1. 南昌航空大學(xué) 航空制造工程學(xué)院，南昌 330063；
2. 南昌航空大學(xué) 材料科學(xué)與工程學(xué)院，南昌 330063)
摘 要: 采用Gleeble-3500型熱模擬機(jī)對Ti-Nb合金在應(yīng)變速率0.001~10 s-1，變形溫度1063~1213 K條件下進(jìn)行熱壓縮實(shí)驗(yàn)，得到流變應(yīng)力曲線。首先采用綜合考慮彈性模量(E)和材料自擴(kuò)散系數(shù)(D)的物理基本構(gòu)方程建立Ti-Nb合金傳統(tǒng)的應(yīng)變補(bǔ)償本構(gòu)模型，再對所建立的本構(gòu)模型進(jìn)行修正來提高預(yù)測該合金流變應(yīng)力的能力，最后對修正的本構(gòu)模型進(jìn)行簡化來進(jìn)一步提升建立該物理基本構(gòu)模型的效率。結(jié)果表明：傳統(tǒng)的應(yīng)變補(bǔ)償本構(gòu)模型的預(yù)測能力并不理想，經(jīng)過修正和簡化的本構(gòu)模型擁有較高的預(yù)測精度且兩者的預(yù)測能力幾乎相同。
關(guān)鍵字: Ti-Nb合金；本構(gòu)關(guān)系；熱變形
（1. School of Aerospace Manufacturing Engineering, Nanchang Hang Kong University, Nanchang 330063, China;
2. School of Materials Science and Engineering, Nanchang Hang Kong University, Nanchang 330063, China）
Abstract:The flow stress curves of Ti-Nb alloy were acquired by hot compressive tests on Gleeble-3500 thermo-simulation machine at the strain rate range of 0.001-10 s-1 and temperature range of 1063-1213 K. Traditional strain compensation constitutive model of Ti-Nb alloy was firstly established by the physically-based equation of elastic modulus (E) and material self-diffusion coefficient (D), and then modified it to improve the predicted ability of flow stress, finally simplified the modified constitutive model to improve the efficiency of building the physically-based constitutive model. The results show that traditional constitutive model does not have good predicted ability, and the prediction abilities of modified and simplified constitutive models are quite excellent and almost identical.
Key words: Ti-Nb alloy; constitutive relationships; hot deformation
