A finite addition of matter elements method for modeling and solution of an SLM thermal problem by a multiscale method

Abstract

In this paper, we are interested in flexible modeling and performing solution of transient thermal Selective Laser Melting Problems. For this, we first introduce a Finite Addition of Matter Elements Method (FAMEM) to generate any wished finite sequence of thermal problems, defined in additively constructed domains. Second, we use the Multiscale Arlequin Frame-work to develop a three-level Arlequin weakstrong formulation of each problem of the finite sequence. Two Arlequin patches are used in the latter to localize the steepest thermal gradients and the nonlinear phase-change phenomena, allowing for fine local approximations and the localized nonlinearity treatment by an algorithm we develop. These patches are identified via the solution of a representative mono-domain transient thermal problem. The latter is also solved with our three-Level Arlequin method for comparison of the solutions and respective performances of both approaches.Moreover, two dimensional tests consisting in the creation of a 316 L stainless steel wall and a two AlSi10Mg layers, are carried out to further enlighten our global approach and to position it with respect to literature.

A Multiscale Method with Continuous Matter Addition in DED Additive Manufacturing Processes

“…To reduce the computational costs, an Arlequin [2,3] based method is presented. To deal with the multi-scale of the problem, the Arlequin method uses two distinct meshes: A coarse mesh of the whole domain and a fine mesh that moves along with the heating source to capture the high thermal gradients near the melt pool.…”

A Simulation Study on the Effect of Residual Stress on the Multi-Layer Selective Laser Melting Processes Considering Solid-State Phase Transformation

“…Among the additive manufacturing technologies, selective laser melting (SLM) possesses high laser power and small laser spot radius, and has become the most widespread, flexible, and economic method within additive manufacturing [ 1 , 2 ]. However, the SLM process is a multi-factor coupling process with powder, laser beam and substrates, and so on, which is a complex metallurgical process involving a moving molten pool, rapid non-equilibrium solidification and solid-phase transformation [ 3 , 4 , 5 ]. During the process, a large amount of thermal residual stresses will be generated which can affect the fracture toughness, crack growth behavior and fatigue performance of the materials [ 6 , 7 , 8 , 9 ].…”