Session: 02-02-02: Characterization of Additively Manufactured Metal Parts

Paper Number: 70091

Start Time: Wednesday, 01:10 PM

70091 - Correlation Between Process Parameters and Fracture Property of 316L Stainless Steel Parts Fabricated by Selective Laser Melting Between Process Parameters and Fracture Properties of 316L Stainless Steel Parts Fabricated by Selective Laser Melting 

Correlation between process parameters and fracture properties of 316L stainless steel parts fabricated by selective laser melting

 

Jianhang Jin, Zhuowen Xie, Guanghui Yang, Wei Jiang

Department of Mechanical Engineering, Dalian University of Technology, Dalian, 116024, China 

Abstract

Selective laser melting (SLM) is an additive manufacturing method in which a metal powder bed is partially melted by a high-energy laser beam. The characteristics of rapid prototyping lead to large thermal gradients and high cooling rates. Improper process parameters may cause structural defects such as pores, impurities, incompletely melted particles and cracks in metal fabricated part. These defects may lead to stress concentration in the fabricated part, and when the stress exceeds the material limit, cracks may be formed,  thus affecting the fracture properties of metal fabricated part. In this study, 316L stainless steel compact tension specimens were fabricated by selective laser melting. Some studies have shown that the mechanical properties of SLM fabricated part are closely related to the laser energy density which is mainly determined by laser power, layer thickness, scanning spacing and scanning rate, and the selection of scanning strategy affects the texture and mechanical properties of SLM fabricated part, which can reduce the deformation of the specimen and make the residual stress lower. However, for laser energy density and scanning strategy, most of the previous studies focused on one of these factors, and mainly focused on some mechanical properties of SLM 316L fabricated part, while few studies on fracture properties were reported. Therefore, in this study, four process parameters including laser power(100 - 200w), scanning rate(500 - 1100mm/s), layer thickness(0.03 - 0.05mm) and scanning strategy(chessboard, stripe, parallel) were selected, and Taguchi experiments with four factors and three levels were designed to study the influence of process parameters on fracture properties of 316L fabricated part. In order to evaluate the fracture properties of 316L fabricated part, tensile tests were carried out on the specimens, and crack opening displacement (COD) was calculated using digital image correlation (DIC) technique. Finally, the correlation between the process parameters and fracture properties was obtained by analyzing the Taguchi experimental data. The research results are helpful to effectively adjust the process parameters to improve the fracture properties of SLM fabricated part, and have reference value for practical engineering applications.

 

Keywords: Selective laser melting, process parameters, fracture property, Taguchi experiment, Crack opening displacement.

Corresponding Author

Wei Jiang, School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China.

Email: jiangwei@dlut.edu.cn

Presenting Author: Zhuowen Xie School of Mechanical Engineering, Dalian University of Technology

Authors:

Jianhang Jin Dalian University of Technolog
Zhuowen Xie Dalian University of Technology
Guanghui Yang Dalian University of Technology
Wei Jiang Dalian University of Technology