Effect of overlap distance on the microstructure and mechanical properties of in situ welded parts built by electron beam melting process

Wang, Pan1; Nai, Mui Ling Sharon1; Sin, Wai Jack1; Lu, Shenglu1; Zhang, Baicheng1; Bai, Jiaming1,2; Song, Jie1; Wei, Jun1

2019-01-25

10.1016/j.jallcom.2018.09.093

JOURNAL OF ALLOYS AND COMPOUNDS   Impact Factor & Quartile

0925-8388

1873-4669

Electron Beam Melting (EBM), one of the powder bed-based additive manufacturing processes that is able to produce complex geometrical metal parts directly, has many application possibilities in various fields. However, an issue has been raised when we apply the EBM technology to fabricate medium volume components. Lack of energy when the scanning line is longer than 100 mm results in the lack-of-fusion pores, which degrades the mechanical properties of the printed part dramatically. Therefore, we propose an in situ welding process to overcome the issue. In order to further understand the microstructure and mechanical properties resulting from the in situ welded process with various overlap distances, we evaluate a series of overlap distances and successfully fabricate a big plate with dimensions of 200 x 200 x 4 mm(3). It is suggested that the defects and microstructure vary according to the overlap distance. Optimized overlap distances are 0.25-0.75mm for Ti-6Al-4V. Within this range, no microstructural variation is observed which results in constant microhardness and superior mechanical properties of the EBM-built component. An overlap distance > 1.5 mm results in microstructure coarsening and mechanical property degradation in the overlap zone. Furthermore, the localized deformation mechanism is discussed based on the findings of the tensile properties and digital image correlation analysis. (C) 2018 Elsevier B.V. All rights reserved.

Titanium alloy Microstructure Mechanical properties Additive manufacturing Digital image correlation

SCI ; EI

English

Others

A*STAR Additive Manufacturing Center (AMC) Initiative: Work Package 1 (High Temperature Materials Development for 3D Additive Manufacturing)[1426800088]

Chemistry ; Materials Science ; Metallurgy & Metallurgical Engineering

Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:000449651100030

ELSEVIER SCIENCE SA

20183805825518

3D printers ; Coarsening ; Electron beam melting ; Electron beams ; Image analysis ; Microstructure ; Strain measurement ; Titanium alloys ; Welding

Welding:538.2 ; Titanium and Alloys:542.3 ; Printing Equipment:745.1.1 ; Mechanical Variables Measurements:943.2 ; Materials Science:951

MATERIALS SCIENCE

Web of Science

1.Singapore Inst Mfg Technol, 73 Nanyang Dr, Singapore 637662, Singapore
2.South Univ Sci & Technol China, Dept Mech & Energy Engn, 1088 Xueyuan Rd, Shenzhen 518055, Guangdong, Peoples R China

Wang, Pan,Nai, Mui Ling Sharon,Sin, Wai Jack,et al. Effect of overlap distance on the microstructure and mechanical properties of in situ welded parts built by electron beam melting process[J]. JOURNAL OF ALLOYS AND COMPOUNDS,2019,772:247-255.

Wang, Pan.,Nai, Mui Ling Sharon.,Sin, Wai Jack.,Lu, Shenglu.,Zhang, Baicheng.,...&Wei, Jun.(2019).Effect of overlap distance on the microstructure and mechanical properties of in situ welded parts built by electron beam melting process.JOURNAL OF ALLOYS AND COMPOUNDS,772,247-255.

Wang, Pan,et al."Effect of overlap distance on the microstructure and mechanical properties of in situ welded parts built by electron beam melting process".JOURNAL OF ALLOYS AND COMPOUNDS 772(2019):247-255.