Achieving ultrafine grained structure in Ti-6Al-4V alloy by high strain rate deformation with a martensitic microstructure
Achieving ultrafine grained structure in Ti-6Al-4V alloy by high strain rate deformation with a martensitic microstructure
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通过具有马氏体微观结构的高应变率变形在 Ti-6Al-4V 合金中实现超细晶粒结构
DOI：
10.1016/j.matlet.2019.04.110
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发表时间：
2019
影响因子：
3
通讯作者：
Sun Jingli
中科院分区：
文献类型：
--
作者：
Zhang Zhixiong;Wang Tao;Han Jianchao;Ren Zhongkai;Wu Ruirui;Sun Jingli
在这项工作中，通过高应变速率（10 s−1）形变，在Ti-6Al-4V中获得了平均晶粒尺寸为0.5 μm的均匀无缺陷超细晶组织，并具有马氏体组织。在初始阶段，马氏体分解为细小的片状α + β组织，促进了动态再结晶（DRX）。随着外加应变的增加，α层片内部形成亚结构，并通过连续动态再结晶（CDRX）逐渐转变为新的超细晶。同时，β相在马氏体分解过程中在互变板条边界上形核形成。研究表明，α′/α + β相转变对超细晶的形成有重要作用。
In this work, a homogeneous defect-free ultrafine grained microstructure with an average grain size of 0.5 μm was achieved in Ti-6Al-4V via high strain rate (10 s−1) deformation with a martensitic microstructure. At the initial stage, the ά martensite decomposed into fine lamellar α + β structures, leading to promotion of dynamic recrystallization (DRX). With the imposed strain increasing, substructures formed inside α lamellae and gradually transformed to new ultrafine grains through continuous dynamic recrystallization (CDRX). At the same time, β phase nucleated and formed on the intervariant lath boundaries during the decomposition of ά martensite. This study indicated that the phase transformation of α′/α + β strongly contribute to the achievement of ultrafine grains.