Fabrication of stainless steel 308L wall through wire + arc additive manufacturing: Microstructure and numerical prediction of tensile test

Abstract

The purpose of this study is to provide functional knowledge on finite element simulation of additively manufactured SS308L plate fabricated through wire + arc additive manufacturing for nuclear and pressure vessel application. To overcome the limitations of conventionally fabricated plates, a wall is built using ideal process parameters identified through trial-and-error experiments. The wall exhibits dendritic (columnar and equiaxed) microstructure, which enhances the tensile strength. The enhancement in strength is evident as the wire + arc additive manufacturing-processed plate exhibited 642 ± 5 MPa while the wrought alloy exhibited 615.7 ± 8 MPa. Finite element simulation was used successfully to simulate the tensile test, and outcomes were predicted with an error percentage of less than 1. The enhancement in strength is due to changes in microstructure and the presence of residual δ-ferrite as evidenced by using evaluation of ferrite number. The ferrite number of a wall from top to bottom varied from 5.0 to 5.3.