Abstract
Wire and arc additive manufacturing (WAAM) is a novel technique for fabricating large and complex components applied in the manufacturing industry. In this study, a low-carbon high-strength steel component deposited by WAAM for use in ship building was obtained. Its microstructure and mechanical properties as well as fracture mechanisms were investigated. The results showed that the microstructure consisted of an equiaxed zone, columnar zone, and inter-layer zone, while the phases formed in different parts of the deposited component were different due to various thermal cycles and cooling rates. The microhardness of the bottom and top varied from 290 HV to 260 HV, caused by temperature gradients and an inhomogeneous microstructure. Additionally, the tensile properties in transversal and longitudinal orientations show anisotropy characteristics, which was further investigated using a digital image correlation (DIC) method. This experimental fact indicated that the longitudinal tensile property has an inferior performance and tends to cause stress concentrations in the inter-layer areas due to the inclusion of more inter-layer zones. Furthermore, electron backscattered diffraction (EBSD) was applied to analyze the difference in Taylor factor between the inter-layer area and deposited area. The standard deviation of the Taylor factor in the inter-layer area was determined to be 0.907, which was larger than that in the deposited area (0.865), indicating nonuniform deformation and local stress concentration occurred in inter-layer area. Finally, as observed from the fracture morphology on the fractured surface of the sample, anisotropy was also approved by the comparison of the transversal and longitudinal tensile specimens.
Highlights
Low-carbon high-strength steel has been applied in many fields such as shipbuilding, automobiles, mining instruments, and railways due to its unique characteristics of mechanical properties and weldability [1]
Conditions after the scanning electron microscope (SEM) analysis, which has a smooth surface and full fusion, there are some oxides or impurities brought from the prepared specimen
A low carbon component with high strength was fabricated by wire and arc additive manufacturing (WAAM) without any visible and an analysis on its component microstructure mechanical was undertaken, In this detects investigation, a low carbon withand high strength properties was fabricated by WAAM
Summary
Low-carbon high-strength steel has been applied in many fields such as shipbuilding, automobiles, mining instruments, and railways due to its unique characteristics of mechanical properties and weldability [1]. The excellent characteristics of CMT make it to be an ideal process for fabricating a large-scale part, which can overcome common troubles encountered during conventional welding process [10,11] In this study, it was adopted as the heat source during the deposition process. Rodrigues et al [15] studied the microstructure and mechanical properties of a high-strength low-alloy (HSLA) steel fabricated by WAAM. A low-carbon high-strength steel developed for ship building was deposited as a thin wall component. It analyzed the surface quality, microstructure evolution, microhardness, and transversal and longitudinal tensile properties. The relationship between fractography and the anisotropy of tensile properties was revealed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
