Abstract

In additive manufacturing, the variation of the fabrication process parameters influences the mechanical properties of a material such as tensile strength, impact toughness, hardness, fatigue strength, and so forth, but fatigue testing of metals fabricated with all different sets of process parameters is a very expensive and time-consuming process. Therefore, the nominal process parameters by means of minimum energy input were first identified for a dense part and then the optimized process parameters were determined based on the tensile and impact toughness test results obtained for 304L stainless steel deposited in laser powder bed fusion (LPBF) process. Later, the high cycle fatigue performance was investigated for the material built with these two sets of parameters at horizontal, vertical, and inclined orientation. In this paper, displacement controlled fully reversed (R = 1) bending type fatigue tests at different levels of displacement amplitude were performed on Krouse type miniature specimens. The test results were compared and analyzed by applying the control signal monitoring (CSM) method. The analysis shows that specimen built-in horizontal direction for optimized parameters demonstrates the highest fatigue strength while the vertical specimen built with nominal parameters exhibits the lowest strength.

Department(s)

Materials Science and Engineering

Second Department

Mechanical and Aerospace Engineering

Research Center/Lab(s)

Intelligent Systems Center

Comments

This research was supported by National Science Foundation Grant CMMI-1625736. Part of the work was also funded by the Department of Energy's Kansas City National Security Campus which is operated and managed by Honeywell Federal Manufacturing Technologies, LLC under contract number DE-NA0002839, Intelligent Systems Center, and Material Research Center at Missouri University of Science and Technology.

Keywords and Phrases

304L Stainless Steel; Additive Manufacturing; Fatigue Test; Impact Toughness Test; Miniature Specimen; Nucleation and Propagation; Simply Supported Bending; Tensile Test

International Standard Serial Number (ISSN)

1996-1944; 1996-1944

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2020 The Authors, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

Publication Date

01 Apr 2020

Share

 
COinS