Additive manufacturing of high-strength weathering steel parts fabricated by gas tungsten arc: Microstructure and mechanical properties

Abstract

This study focuses on microstructure and mechanical properties as a function of location in additively manufactured high-strength weathering steel components using gas tungsten arc as the heat source. Variations of microstructure and mechanical properties in various locations are presented and analysed. The as-deposited high-strength weathering steel is composed of columnar grain morphology with proeutectoid ferrite, acicular ferrite, side plate ferrite and a small amount of pearlite microstructure in the top region, equiaxed grains with ferrite and pearlite in the middle region, and columnar grains in the near-substrate region with the microstructure similar to that in the top region. There exist obvious layer bands in the middle region, and the forming mechanism of the bands is addressed. Microhardness measurement and tensile strength testing indicate obvious changes in different regions, depending on location and direction of testing specimens. The microhardness in the middle region is inferior to that in both near-substrate and top regions. The ultimate tensile strengths in the travel and deposition height directions are approximately 553 and 506 MPa, respectively. Different locations exhibit heterogeneous tensile strength and elongation due to various microstructures and boundaries. The results indicate the feasibility to fabricate high-strength weathering steel components with good tensile properties using gas tungsten arc–based additive manufacturing.

Investigating the relation between debinding atmosphere and mechanical properties of stereolithography-based three-dimensional printed Al2O3 ceramic

“…After sintering, the alumina crystal particles were grown gradually and connect together through strong interaction forces during the sintering process, which lead to the similar shrinkage of the sintered ceramics. [56][57][58]…”

Effect of Modified Water‐Bath Method on Microstructure and Mechanical Properties of Wire Arc Additive Manufactured Low‐Carbon Low‐Alloy Steel

“…Many researches on low‐carbon steel fabricated through WAAM using different depositing strategies have reported that the microstructures of low‐carbon low‐alloy steel are significantly influenced by their unique thermal histories. [ 25–29 ] However, there are few studies on the microstructure of steel fabricated through WAAM using a water bath. In this study, a low‐carbon low‐alloy steel sample is fabricated through GAM‐WAAM using the modified water‐bath method with a changing level as the active cooling approach to realize a high cooling rate, and another sample is fabricated under air cooling for comparison.…”

Effect of laser rescanning on Ti6Al4V microstructure during selective laser melting

“…As for other metal alloys, such as weathering steel, Ni-Ti structure, Inconel-718 alloy, Ni/Febased superalloy, and some other Al alloy have also been studied by some other researchers. [7][8][9][10] Olakanmi et al studied aluminum alloy powder. 11 The process parameters were changed to optimize the microstructure of the parts and different properties of the printed parts can be found in this work.…”