Abstract
Bimetallic additively manufactured structures (BAMSs) can replace traditionally-fabricated functionally-graded-components through fusion welding processes and can eliminate locally-deteriorated mechanical properties arising from post-processing.The present work fabricates a BAMS by sequentially depositing the austenitic stainless-steel and Inconel625 using a gas-metal-arc-welding (GMAW)-based wire + arc additive manufacturing (WAAM) system.Elemental mapping shows a smooth compositional transition at the interface without any segregation.Both materials being the face-center-cubic (FCC) austenite,the electron backscattered diffraction (EBSD) analysis of the interface shows the smooth and cross-interface-crystallographic growth of long-elongated grains in the <001> direction.The hardness values were within the range of 220-240 HV for both materials without a large deviation at the interface.Due to the controlled thermal history,mechanical testing yielded a consistent result with the ultimate tensile strength and elongation of 600 MPa and 40 %,respectively,with the failure location on the stainless-steel side.This study demonstrates that WAAM has the potential to fabricate BAMS with controlled properties.
基金项目
This study has been conducted with the support of the Korea Institute of Industrial Technology as a project on the development o(KITECH JE200008)