Microstructure and Mechanics Property Variations during MDIF of Ti-6Al-4V Alloy with a Martensitic Microstructure

被引：0

作者：

Zhang Z. ^{[1
,2
]}

Zhang J. ^{[1
]}

Han J. ^{[1
,2
]}

Zhang C. ^{[3
]}

Zhang S. ^{[3
]}

Wang T. ^{[1
,2
]}

机构：

[1] College of Mechanical and Delivery Engineering, Taiyuan University of Technology, Taiyuan

[2] Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment, Ministry of Education, Taiyuan University of Technology, Taiyuan

[3] School of Material Science and Engineering, Taiyuan University of Technology, Taiyuan

来源：

| 1600年 / Chinese Mechanical Engineering Society卷 / 32期

关键词：

Grain refinement; Martensite; Mechanics properties; Multidirectional isothermal forging (MDIF); Ti-6Al-4V alloy;

D O I：

10.3969/j.issn.1004-132X.2021.22.011

中图分类号：

学科分类号：

摘要：

The as-cast Ti-6Al-4V alloy was subjected to a heat treatment condition to obtain a typical α' martensitic microstructure. After two-step isothermal forging, a homogeneous equiaxed grained microstructure with an average grain size of 1.5 μm was achieved. The refined microstructure led to a significant mechanics property improvement. The fine grained Ti-6Al-4V alloys exhibited high yield strength(906 MPa), high ultimate tensile strength(954 MPa), and good ductility(16.7%). The finer grain size and better mechanics properties indicate that the phase transformation of α'/α+β strongly contributed to the microstructure refinement during isothermal forging of Ti-6Al-4V alloys. After the first step forging, the microstructure near the center of the forging is highly deformed, while very little deformations are present in the center regions near the die due to the effects of die chilling and friction. After the second step forging, α lamellae are fully globularized and the microstructure is homogeneous. The crystal rotations of the grains near the center are larger than that of the grains in the midway from the center to the outer edge. © 2021, China Mechanical Engineering Magazine Office. All right reserved.

引用

页码：2739 / 2748

页数：9

共 25 条

[1] SUN Jia, LI Xuexiong, ZHANG Jinhu, Et al., Phase Field Simulation of the Formation Mechanism of Grain Boundary α Phase in Ti-6Al-4V Alloy β→α Phase Transition, Acta Metallurgica Sinica, 56, 8, pp. 1113-1122, (2020)
[2] DU Zijie, LI Wenyuan, LIU Jianrong, Et al., Research on the Uniformity and Mechanical Properties of CMT Additive Manufacturing TC4-DT Alloy, Acta Metallurgica Sinica, 56, 12, pp. 1667-1680, (2020)
[3] GAO P F, FU M W, ZHAN M, Et al., Deformation Behavior and Microstructure Evolution of Titanium Alloys with Lamellar Microstructure in Hot Working Process: a Review, Journal of Materials Science & Technology, 39, pp. 56-73, (2020)
[4] ZHANG W J, DING H, PEREIRA P H R, Et al., Grain Refinement and Superplastic Flow in a Fully Lamellar Ti-6Al-4V Alloy Processed by High-pressure Torsion, Materials Science and Engineering: A, 732, pp. 398-405, (2018)
[5] ZHANG Z X, QU S J, FENG A H, Et al., Hot Deformation Behavior of Ti-6Al-4V Alloy: Effect of Initial Microstructure, Journal of Alloys and Compounds, 718, pp. 170-181, (2017)
[6] SHENG J W, WANG Z Y, ZHENG L H, Et al., Characterization of Microstructure and Texture Evolution in Ti664 Titanium Alloy after Multidirectional Forging and Annealing Treatments, Journal of the Minerals, Metals & Materials Society, 71, 12, pp. 4687-4695, (2019)
[7] ZHANG Z X, QU S J, FENG A H, Et al., The Low Strain Rate Response of As-cast Ti-6Al-4V Alloy with an Initial Coarse Lamellar Structure, Metals, 8, 4, pp. 1-13, (2018)
[8] KUMAR P, PRAKASH O, RAMAMURTY U., Micro-and Meso-structures and Their Influence on Mechanical Properties of Selectively Laser Melted Ti-6Al-4V, Acta Materialia, 154, pp. 246-260, (2018)
[9] JOVANOVIC M T, TADIC S, ZEC S, Et al., The Effect of Annealing Temperatures and Cooling Rates on Microstructure and Mechanical Properties of Investment Cast Ti-6Al-4V Alloy, Materials and Design, 27, 3, pp. 192-199, (2006)
[10] SESHACHARYULU T, MEDEIROS S C, FRAZIER W G, Et al., Microstructural Mechanisms during Hot Working of Commercial Grade Ti-6Al-4V with Lamellar Starting Structure, Materials Science and Engineering: A, 325, 1, pp. 112-125, (2002)

← 1 2 3 →