Effects of mechanical properties on precipitation hardening stainless steel by selective laser melting, hot isostatic pressing, solid-solution and aging treatments

ABSTRACT

The selective laser melting (SLM) process has gained considerable attention from industry and academia over the recent years. Furthermore, the hot isostatic pressing (HIP) technique has been widely applied as a post-treatment to increase the relative density of the fabricated parts. The main aim of this study is to investigate the effects of porosity elimination and mechanical properties on precipitation hardening stainless steel using SLM, HIP, solid-solution and aging treatments. This study also applied various laser scanning pitches (170, 210 and 250 μm), so that a significant phase transformation occurred between the SLM, HIP, solid-solution and aging treatments. The results showed that the laser scanning pitch was 170 μm, and after HIP, solid-solution and aging treatments the materials possessed optimal mechanical properties. The highest hardness (48.8 ± 0.5 HRC) and TRS (2247.0 ± 157.8 MPa) could be acquired.

KEYWORDS:

• Selective laser melting
• hot isostatic pressing
• precipitation hardening stainless steel
• phase transformation
• solid-solution
• TRS

Acknowledgements

The authors would like to express their appreciation for Mr. Chih-Kai Wang, Mr. Chun-I Lee, Michael Liao and Mr. Meng-Yu Liu.

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Shih-Hsien Chang: 1993–1995, M.S. in Materials Science and Engineering, National Cheng Kung University; 2001–2006, Ph.D. in Materials Science and Engineering, National Cheng Kung University; Feb. 2015–present, Professor, Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taiwan, ROC.

Yi-Min Liu: 2015–2019, B.Sc. in Department of Materials and Mineral Resources Engineering, National Taipei University of Technology; Jul. 2019–present, Project Engineer, voestalpine Technology Institute (Asia) Co. Ltd., Taiwan, ROC.

Kuo-Tsung Huang: 2001–2007, Ph.D. in Materials Science and Engineering, National Cheng Kung University; Aug. 2001–present, Lecturer, Department of Auto-Mechanics, National Kangshan Agricultural Industrial Senior High School, Kaohsiung, Taiwan, ROC.

Shang-Chih Wang: 2007, Ph.D. in Mechanical Engineering, National Chiao-Tung University; 1993–2015, Researcher, Industrial Technology Research Institute; 2015–2017, R&D Director, Wire Technology Co. Ltd.; 2017–present, Managing Director, voestalpine Technology Institute (Asia) Co. Ltd., Taiwan, ROC.

Additional information

Funding

This research is provided by the Voestalpine Technology Institute (Asia) Co., Ltd. and Assab Steels Taiwan Co., Ltd.