Multiscale analysis of mechanical behavior of multilayer steel structures fabricated by wire and arc additive manufacturing

Abstract

The mechanical behavior of multilayer steel structures fabricated via wire and arc additive manufacturing (WAAM) has been investigated from the multiscale perspective. The multimaterial WAAM approach can control a heterogeneous structure and improve its mechanical properties. In this study, WAAM equipment based on plasma arc welding was used to fabricate two pairs of single-and duplex-phase multilayer steel structures using austenitic and martensitic stainless steel wires. The heterogeneity of these structures was characterized through micro-indentation tests. In addition, tensile tests of the multilayer structures were conducted to evaluate the effect of heterogeneity on macroscopic material properties. The deformation behavior of the heterogeneous multilayer steel structures was investigated by comparison with the finite element simulations of tensile tests in which the finite element models were created according to the estimated local elastoplastic properties from the results of micro-indentation tests. The microindentation tests revealed that the local mechanical properties significantly change during WAAM in cases where martensitic stainless steel wire was used. Additionally, strain-induced transformation plasticity was particularly observed in duplex cases, caused by the metastable austenite phase formed according to the thermal history and through the mixing of alloy elements. Thus, the heterogeneity of the multilayer steel structures became more complicated than its design, and consequently, its macroscopic mechanical properties exceeded the upper and lower bounds of a micromechanic estimation. The results show the potential to fabricate a structure having a unique mechanical behavior via the multimaterial WAAM approach.

Large‐scale failure prediction of clay rock from small‐scale damage mechanisms of the rock medium using multiscale modelling

“…An exhaustive literature review about the above topics is presented in Zhang et al 27 . For other (civil) engineering applications, the mechanical behaviour of advanced composite materials 28,29 and multi‐layered anisotropic structures 30 has also been modelled though multiscale approaches. Specifically, for geomaterials, macroscale FEM are often combined with discrete or finite element methods (respectively, DEM or FEM) at smaller scale, depending on the structure at small scale.…”

“…26 Other multiscale FEM studies focus on the heterogeneous medium, permeability variation, structures with random porosity structures or internal crack, studies include simulation problems in fractured porous media, of transport problems. An exhaustive literature review about the above topics is presented in Zhang et al 27 For other (civil) engineering applications, the mechanical behaviour of advanced composite materials 28,29 and multi-layered anisotropic structures 30 has also been modelled though multiscale approaches. Specifically, for geomaterials, macroscale FEM are often combined with discrete or finite element methods (respectively, DEM or FEM) at smaller scale, depending on the structure at small scale.…”

Wall Fabrication by Direct Energy Deposition (DED) Combining Mild Steel (ER70) and Stainless Steel (SS 316L): Microstructure and Mechanical Properties

“…Inconel718-austenitic SS combination has been employed in the aeronautic sector and in some nuclear power plants [ 9 , 10 ]. Regarding steels, different types of them can be combined in function of the desired properties, for example, low carbon steel with austenitic stainless steel [ 3 ], maraging steel with tool steel [ 11 ], ferritic steel with austenitic steel [ 12 ] or martensitic with austenitic stainless steels [ 13 ]. M. Ahsan et al [ 14 ] fabricated a BMS from low-carbon steel (LCS) and austenitic stainless steel and then heat-treated it.…”

Data-driven estimation of plastic properties of alloys using neighboring indentation test

“…In this context, the hardness test, in which the resistance to the imposed plastic deformation is measured on the surface, has been utilized as an efficient approach to estimate the mechanical properties in the industry. It can be used also to evaluate small-scale mechanical properties by controlling a small load; that is, the mechanical properties of a heterogeneous microstructure can be evaluated [1][2][3]. Using this technology, highthroughput evaluation of microscopic mechanical properties has been conducted to characterize the microscopic heterogeneity [4,5] and obtain massive material data [6].…”