基于Murty判据的Ti-6.5Al-3.5Mo-1.5Zr-0.3Si钛合金α β相区热变形机制及工艺优化

Hot Deformation Mechanism and Process Optimization for Ti-Alloy Ti-6.5Al-3.5Mo-1.5Zr-0.3Si duringα β Forging Based on Murty Criterion

摘要:

根据Murty失稳判据,利用原始等轴组织的TC11钛合金在780～990℃和0.001～70s-1范围内的等温恒应变速率压缩实验数据,建立了该合金的加工图.依据加工图研究了TC11钛合金的变形机制和变形缺陷与变形热力参数之间的关系.结果表明,在780～990℃和0.001～0.01 s-1范围是超塑性变形区;在780～990℃和高于0.01 s-1范围,易出现β相裂纹和空洞、局部流动以及绝热剪切等流变失稳现象.根据加工图分析,结合微观组织观察结果,并考虑变形抗力的大小,确定出了较佳的变形热力参数范围为850～940℃和0.001～0.01 s-1,最佳的变形热力参数在900℃和0.001 s-1附近.

关键词:钛合金;Ti-6.5Al-3.5Mo-1.5Zr-0.3Si;工艺优化;Murty失稳判据;变形机制;Ti-alloy;Ti.6.5Al-3.5Mo-1.5Zr-0.3Si;process optimization;Murty instability criterion;deformation mechanism;判据;钛合金;β相;热变形机制;工艺优化;Process Optimization;Deformation Mechanism;during;Criterion;Based;optimum;parameters;flow stress;status;localization;adiabatic;shear bands;above;phase;instability

Abstract:

Key words:Ti-alloy;Ti.6.5Al-3.5Mo-1.5Zr-0.3Si;process optimization;Murty instability criterion;deformation mechanism