Selective laser melting of novel duplex stainless steel matrix composites with high strength and ductility for multi-performance metallic foam sandwich in extreme environment
Abstract
As the interest and demand for space applications are on the rise, some of space parts for harsh environment have been spotlighted, which have outstanding mechanical properties to protect inner payloads or crews. Therefore, the relevant materials such as aluminum-titanium alloy have been widely studied for the space application. However, stainless steel alloy has been rarely used for the application despite its cheap price and high mechanical properties. This is because stainless steel has a higher density than that of the aluminum-titanium alloy. Therefore, in this project, additive manufacturing of lightweight sandwich structure, which is made of a novel stainless steel, is suggested for the space application in harsh environment. This project aims to develop and additively manufacture the novel duplex stainless steel (DSSs) composite, and demonstrate the metallic foam sandwich using the material. First, DSS-TiC compsites and super austenitic stainless steel (SASS)-TiC composites will be investigated for obtaining a desirable phase ratio and resultant mechanical property. Next, a process optimization of selective laser melting (SLM) process and post heat treatment will be conducted to refine their microstructure. Then, a novel DSS matrix composites will be developed through SLM of a powder mixture of DSS, SASS, and TiC, along with a subsequent quenching process. The high strength and ductility will be obtained due to the formation of fine ferrite grains and bimodal (fine + coarse) austenite grains. Finally, a metallic foam sandwich will be demonstrated through the SLM of the composite, exhibiting a lightweight, high strength, good vibration attenuation, and excellent impact resistance, etc. The novel SLM material and structures will be used for various space applications which require strict performance in extreme environments.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 16, 2024
- Source ID
- FA23862314043
Entities
People
- Il Yub Choi
Organizations
- Air Force Office of Scientific Research
- Sungkyunkwan University
- United States Air Force