Influence of heat accumulation on microstructure and property of Ti-6Al-4V in laser direct forming

SHI Bofei; ZHANG Anfeng; QI Baolu; LI Dichen

doi:10.7510/jgjs.issn.1001-3806.2016.01.007

In order to study effect of heat accumulation on microstructure and mechanical property of Ti-6Al-4V, two cylindrical samples and two tensile samples in 5mm and 10mm diameters of were made by means of laser direct forming. Heat accumulation was intense while forming 5mm sample. Martensite ' was found inside grains at the bottom and top positions, while acicular was found inside grains in the middle position. Heat accumulation was weak while forming 10mm sample. Martensite ' was found from the bottom to the top position. The samples of intense heat accumulation had a slightly weak tensile strength and three times of tensile plasticity. Experiment results show that intense heat accumulation while forming Ti-6Al-4V would make cooling rate decreased and microstructure would transform from martensite ' to acicular so that the tensile strength decreases and the tensile plasticity increases.

Influence of heat accumulation on microstructure and property of Ti-6Al-4V in laser direct forming

Corresponding author: ZHANG Anfeng, zhangaf@mail.xjtu.edu.cn;

1. State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054, China

Received Date: 2014-12-09

Accepted Date: 2014-12-25

Available Online: 2016-01-25

Abstract: In order to study effect of heat accumulation on microstructure and mechanical property of Ti-6Al-4V, two cylindrical samples and two tensile samples in 5mm and 10mm diameters of were made by means of laser direct forming. Heat accumulation was intense while forming 5mm sample. Martensite ' was found inside grains at the bottom and top positions, while acicular was found inside grains in the middle position. Heat accumulation was weak while forming 10mm sample. Martensite ' was found from the bottom to the top position. The samples of intense heat accumulation had a slightly weak tensile strength and three times of tensile plasticity. Experiment results show that intense heat accumulation while forming Ti-6Al-4V would make cooling rate decreased and microstructure would transform from martensite ' to acicular so that the tensile strength decreases and the tensile plasticity increases.

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Reference (17)

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Influence of heat accumulation on microstructure and property of Ti-6Al-4V in laser direct forming

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