A study on wire and arc additive manufacturing of low-carbon steel components: process stability, microstructural and mechanical properties

Abstract

Among metal-based additive manufacturing, wire and arc additive manufacturing is receiving increasing attention for the production of components with medium to large dimensions. In the current research, the production of low-carbon steel thin-walled components by wire and arc additive manufacturing was addressed. Firstly, the influence of two depositing direction strategies on the wall shape was investigated. Subsequently, the effect of heat input on the shape stability and the microstructure evolution of the walls was studied. The results indicated that the alternating depositing direction strategy was more suited to build thin walls with relatively regular height. The heat input significantly influenced the shape stability, but had slight effects on the microstructure evolution. The microstructure of the walls varied from the top to the bottom regions, leading to a variation in hardness from 157 ± 3.11 to 192 ± 4.30 (HV5). The microstructure of the built thin walls can be distinguished in three regions: The upper region exhibited lamellar structures; the middle region dominantly featured granular structures of ferrites with a small proportion of pearlites, which appear in the boundaries of grains; and the lower region showed a mix of lamellar and equiaxed structures of ferrites. The tensile properties of the built material also exhibited anisotropic characteristics: The yield strength and ultimate tensile strength vary from 320 ± 6 to 362 ± 8 MPa and from 429 ± 8 to 479 ± 7 MPa, respectively.

Description of anisotropic material response of wire and arc additively manufactured thin-walled stainless steel elements

“…These barriers relate, to a large extent, to the scarcity of test data on the mechanical properties and structural performance of additively manufactured materials [12,13,14]. In light of this, there has recently been a growing number of research groups investigating the microstructural and mechanical properties of different WAAM materials, including lowalloy steels [15,16,17,18,19] and various stainless steel alloys [20,21,22,23,24,25,26,27]. The aforementioned studies have revealed a degree of anisotropy in the behaviour of WAAM stainless steel material, i.e.…”

Influence of the WAAM process and design aspects on residual stresses in high-strength structural steels

“…Essential attributes for an AM component are the resulting mechanical properties of the final product. These properties depend substantially on the thermal history of the material and relate with the microstructure, toughness, and the material [1,12,13]. For additive manufacturing, the knowledge of multilayer welding can be adapted with a few modifications.…”

Optimization of Weld Parameters in Wire and Arc-Based Directed Energy Deposition of High Strength Low Alloy Steels

“…Most of the previously mentioned studies have selected the process variables (e.g., the arc voltage, welding current, and wire-feed speed) based on the suggestion of the wire manufacturers for conventional welding or based on several tests, while the WADED process is very different from welding. In WADED processes, the quality and geometry of weld beads (e.g., stable and smooth shape and less spatter) notably affect the process stability and the appearance of as-fabricated components [22][23][24][25]. Therefore, this study aims to explore the relationship between the process variables {C, U, and V} and the geometrical characteristics of weld beads {BW, BH, and MPL} and identify optimal process parameters that produce weld beads with expected geometrical properties.…”