等温锻造应变速率对Ti60合金组织和性能的影响

Effect of Strain Rate on Microstructure and Properties of Ti60 Alloy Under Isothermal Forging

为了确定Ti60合金的最佳等温锻造工艺参数,研究了8×10-4s-1、3×10-3s-1、8×10-3s-1三种应变速率对其组织和性能的影响。结果表明:随着应变速率的提高,合金组织中初生α相比例递减,等轴化程度逐渐提高,尺寸趋于均匀,片状次生α相由短小弥散状向细长状发展;合金强度呈先减少后增加的趋势,室温塑性则先增加后减少,高温塑性递减且高温塑性较室温塑性对应变速率更为敏感。应变速率为8×10-3s-1时的等温锻件性能较好地符合600℃用钛合金盘件的使用性能,确定其为Ti60合金最佳的等温锻造应变速率。

The effect of strain rate （8 × 10^-4 s^-1, 3 × 10^-3 s^-1, 8 × 10^-3 s^-1 ） on microstructure and properties of Ti60 alloy under isothermal forging was studied. The results show that isothermal forging strain rate has obvious influence on microstructure and properties of Ti60 alloy. The volume fraction of the primary-a phases decreases with the increase of sWain rate and the grain size becomes uniform graduaUy; the lamellar secondary-or is short and small firstly and then slender; the strength decreases firstly and then increases, while the room temperature ductility changes on the contrary; the high temperature ductility decreases with the increase of swain rate and is more sensitive to swain rate than the room temperature ductility. The properties of the isothermal forging at the strain rate of8×10^-3 s^-1 are more suitable for the 600℃ titanium disk, so 8×10^-3s^-1 is the best strain rate.