等温校正+固溶时效热处理工艺对改善叶片型面和组织性能的影响

Research on the Technical Scheme of Isothermal Adjustment and Solution Plus Aging Heat Treatment to Improve Blade Profile and Mechanical Properties

针对TC11钛合金叶片锻造变形后的残余应力和冷却时的温度应力叠加造成的叶身型面翘曲问题,采用等温校正的方法来释放残余应力,使翘曲变形减轻,叶片尺寸达到合格,同时保证叶片的金相组织和力学性能得到改善。校正实验结果表明,采取等温校正+固溶时效热处理工艺得到的叶片型面、力学性能和金相组织,优于仅固溶热处理而未进行校正的叶片;随着校正温度的提高,叶片校正效果越来越明显,当校正温度提高到900℃时,等温校正型面透光度最小;叶片等温校正+固溶时效热处理的最佳组合工艺方案为860℃时,校正压力为3 MPa,保压时间3 min,应变速率10-2(S-1)。

In this paper, the isothermal adjustment method is adopted for reducing the residual stress of as-forged and the temperature stress during heat treatment. The adjustment experimental result indicates that TC11 alloy blade which adopts adjustment and solution plus aging heat treatment have better transmissivity of blade profile, the mechanical property and microstruture than that blade which only adopts solution heat processing technical scheme; In the isothermal adjustment, the improvement of blade profile become more and more obvious as the adjustment temperature increasing, mininum the transmissivity of blade profiles is reached when the adjustment temperature up to 900℃. The best technical scheme of blade adjustment is A2B2C1D2 according to range and variance analysis, that is to say, under the condition of 860℃, 3 MPa adjustment pressure, 3 min pressure maintaining time and 10^-2（S^-1） strain rate.