后处理对退火态TC4 ELI合金显微组织与性能的影响
Effect of post heat treatment on the microstructure and properties of as-annealed TC4 ELI alloy
尹艳超 1孙志杰 1薛达 1锁永永 1刘海彬1
作者信息
- 1. 中国船舶集团有限公司第七二五研究所,河南洛阳 471023
- 折叠
摘要
采用光学金相显微镜(OM)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、室温拉伸、夏比冲击试验研究了后处理工艺对退火态TC4 ELI合金显微组织和力学性能的影响.结果表明,退火态TC4 ELI合金经520～720℃时效处理后发生"双态→等轴"的逆转变现象,强度呈现先升高后降低的趋势;冲击功在560℃降至最低后随温度升高稍有提高;时效α相的出现是冲击韧性劣化的主要原因,α2相析出的影响则较小.620℃时效态TC4 ELI合金经高温处理后,强度略微升高;温度升至β相区时,组织粗化造成屈服强度突降,晶界α相的出现引起塑性突降;高温处理后,时效α相消失,冲击功得到较大程度的恢复.
Abstract
The effects of post heat treatment on the microstructure and mechanical properties of an-nealed TC4 ELI alloy investigated by optical microscopy(OM),transmission electron microscopy(TEM),scanning electron microscopy(SEM),tensile and Charpy impact test at room temperature.The results show that the"bimodal → equiaxed"reverse transformation occurs in the annealed TC4 ELI al-loy after aging at 520-720 ℃,and the strength increases first and then decreases.The impact toughness of the annealed TC4 ELI alloy decreases to the lowest value at 560 ℃,then increases slightly with the increase of temperature.The appearance of aging α phase is the main reason for the deterioration of im-pact toughness,while the precipitation of α2 phase has little effect.The strength of TC4 ELI alloy aged at 620 ℃ increases slightly after high temperature treatment.When the temperature rises to the β phase region,the coarsening of the microstructure causes a sudden drop in yield strength,and the appearance of the α phase at the grain boundary causes a sudden drop in plasticity.After high temperature treat-ment,the aging α phase disappears,and the impact toughness is recovered to a greater extent.
关键词
退火态TC4/ELI合金/后处理/显微组织/强度/冲击韧性Key words
annealed TC4 ELI titanium alloy/post heat treatment/microstructure/strength/impact toughness引用本文复制引用
基金项目
中国船舶七二五所科技创新项目(LW230803)
出版年
2024
国家科技期刊平台
NSTL
万方数据