固溶冷却方式对新型高强近β钛合金Ti-5321微观组织及力学性能的影响  

Effect of Cooling Method After Solution on Microstructure and Mechanical Properties of New Near-βTi Alloy Ti-5321

作　　者：宋博 安明宇 王红阳 王一森 甄金明 SONG Bo;AN Mingyu;WANG Hongyang;WANG Yisen;ZHEN Jinming(School of Materials Science and Engineering,Liaocheng University,Liaocheng 252059,China)

机构地区：[1]聊城大学材料科学与工程学院,山东聊城252059

出　　处：《聊城大学学报（自然科学版）》2024年第3期53-61,共9页Journal of Liaocheng University:Natural Science Edition

基　　金：国家自然科学基金项目(52105190);山东省自然科学基金资助项目(ZR2022QE115);聊城市重点研发计划政策引导类项目(2022YDSF85);聊城大学大学生创新创业训练计划项目(CXCY2023029)资助。

摘　　要：以新型高强近β钛合金Ti-5Al-3Mo-3V-2Cr-2Zr-1Nb-1Fe(Ti-5321,式中数值为对应元素的质量分数的100倍)为实验材料,研究了固溶冷却方式对钛合金组织演变、相变过程及力学性能的影响。结果显示合金固溶后经不同方式冷却会形成不同类型的组织,在连续加热过程中发生不同的相变,导致时效后α相析出特征明显不同,合金具有不同力学性能。Ti-5321合金固溶后空冷,β相基体中会形成ω和O′两种亚稳相。与水淬态样品相比,空冷态样品时效处理后α相尺寸更小,密度更高,析出强化效果也更高。当时效温度为600℃时,空冷态合金时效后的抗拉强度最高,达到1421 MPa,水淬态合金的抗拉强度为1220 MPa。合金固溶后炉冷α相以板条状析出,形成网篮组织,时效处理不改变组织特征,合金强度最低,塑性最好。Influence of cooling method after solution on microstructure evolution,phase transformation and mechanical properties of new hi gh strength Ti alloy Ti-5Al-3Mo-3V-2Cr-2Zr-1Nb-1Fe(these values are mass fraction multiplied by 100,Ti-5321)was studied in this work.The results showed that different microstructures were developed depending on solution cooling method.The samples under different cooling conditions experienced different phase transformation processes,leading toαprecipitates exhibiting different characters after aging treatment and finally obtained different properties.For the air cooled sample,two types of intermediate phasesωand O′would be formed inβmatrix.In comparison with the water quenched sample,the air cooled sample developedαprecipitates having smaller size and larger number density,as well as stronger precipitation hardening effect.When aged at 600℃,the air cooled sample obtained highest ultimate tensile strength 1421 MPa,and the strength of water quenched one was 1220 MPa.In the furnace cooled sample,theseαprecipitates presented plate-like shape,forming basketwave microstructure.It could not be affected by aging treatment,and the furnace cooled alloy had lowest strength and best ductility.

关 键 词：钛合金 冷却方式 微观组织 力学性能 

分 类 号：TG166.9[金属学及工艺—热处理]