Effects of heating rate on the alloy element partitioning and mechanical properties in equiaxed α+β Ti-6Al-4V alloy

• 作者: Jinhu Zhang Hongtao Ju Haisheng Xu Liang Yang Zhichao Meng Chen Liu Ping Sun Jianke Qiu Chunguang Bai Dongsheng Xu Rui Yang
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（35）
• 页码范围: 1-9
• 页数: 9页
• 语种: 英文

摘要

The effects of heating rate on the alloy element partitioning and mechanical properties during the phase transformation of α-→β in Ti-6Al-4 V alloy under solution treatment have been investigated by the ex-periments and phase field simulations,which reveal the evolutions of microstructure and compositions at the non-equilibrium state and well verify the experimental results.The specific results indicate that the compositions measured through electron probe micro-analysis (EPMA) under a lower heating rate are close to the equilibrium ones corresponding to the solution temperature.Heating up to the target solution temperature,as the heating rate increases,the Al content decreases and V increases in the pri-mary α (αp) grain with a larger size,the volume fraction of αp increases and the composition gradient between αp and β phases gets steeper.The interrelated relationship among the diffusion,compositions,solution temperature and free energy of the system has been discussed in detail.Moreover,increasing the heating rate (～20.0 K/min) may help to improve the mechanical properties of the alloy by mainly adjusting the αp/βt volume fractions,αp particle size and secondary α (αs) size during the process of heating up to the solution temperature.These results may shed some light on the optimization of the knowledge-based heat treatment route.