Microstructure and Mechanical Properties of Friction Stir Welded and Laser Welded High Entropy Alloy CrMnFeCoNi
Microstructure and Mechanical Properties of Friction Stir Welded and Laser Welded High Entropy Alloy CrMnFeCoNi
- 주제(키워드) high entropy alloy , friction stir welding , laser welding , microstructure , mechanical property
- 발행기관 대한금속·재료학회
- 발행년도 2018
- 총서유형 Journal
- KCI ID ART002304350
- 본문언어 영어
초록/요약
The high entropy alloy CrMnFeCoNi has been shown to have promising structural properties. For a new alloy to beused in a structural application it should be weldable. In the present study, friction stir welding (FSW) and laserwelding (LW) techniques were used to butt weld thin plates of CrMnFeCoNi. The microstructure, chemical homogeneityand mechanical behavior of the welds were characterized and compared with the base metal. The tensilestress-strain behavior of the welded specimens were reasonable when compared with that of the base metal. FSWrefined the grain size in the weld region by a factor of ~14 when compared with the base metal. High-angle annulardark field transmission electron microscopy in combination with energy dispersive X-ray spectroscopy showedchemical inhomogeneity between dendritic and interdendritic regions in the fusion zone of LW. Large fluctuationsin composition (up to 15 at%) did not change the crystal structure in the fusion zone. Hardness measurementswere carried out in the weld cross section and discussed in view of the grain size, low angle grain boundaries andtwin boundaries in FSW specimens and the dendritic microstructure in LW specimens.
more