Effects of current stressing on properties and microstructure of Inconel 600 alloy

Abstract

This study investigated the mechanism of the properties and microstructure variation on Inconel 600 alloy after current stressing The strip specimens were subjected to a fixed 7000 A/cm? D C current with different stressing time (tD) and stressing cycles (N) combination The specimens were rapidly quenched with liquid nitrogen after current stressing to freeze the microstructure for investigation The variation of properties and microstructure were discussed with the stressing parameter tD/N The results of XRD EPMA and EDS confirmed second phase and precipitate would not emerge under current stressing EBSD figures showed grain growth and twin formation after current stressing The increase of the fraction of high angle grain boundaries also indicated the potential of recrystallization and grain growth The lattice arrangement which was observed with HRTEM was disturbed by the electron wind force and influenced the dislocation density Different stressing conditions (stressing time and stressing cycles) that provided Joule heat and electron wind force resulted in the elimination and rebirth of the dislocation The mechanical and electrical properties of the Inconel 600 strips were investigated using Vickers micro-hardness tester and 4-point probe respectively The variation of micro-hardness was highly related to the dislocation Micro-hardness variation was ascribed to strain hardening The resistivity declined to different extent after current stressing The resistivity was affected by the grain size and twin formation but the former dominated the variation

Date of Award	2020
Original language	English
Supervisor	Kwang-Lung Lin (Supervisor)