Selective Laser Melting (SLM) is a type of additive manufacturing process that begins with placing a layer of powder onto a solid substrate. A laser beam traverses the surface of the powder layer along a predefifined profifile. The intense heat generated by the laser beam causes powder particles to melt and to form a melt pool which solidififies as a fused layer of material. This mechanism operates over the entire layer according to the need and is repeated for each subsequent layer until the desired product is attained. SLM can manufacture the fifinal geometry with part density similar to that of the bulk solid. SLM has a wide range of potential applications in aerospace, tooling, automotive and prototyping industries. SLM is also used in manufacturing of orthopaedic and dental bio-implants, where porous titanium structures are used and also in stainless steel sandwich structures where remarkable progress has been achieved.

SLM process involves interaction with very high energy beam and high temperature gradients causing the problem of thermal distortion, balling and the formation of cracks in the product. Temperature gradients within the melt pool cause a surface tension driven flfluid flflow from regions with low surface tension to regions with high surface tension, known as Marangoni convection. It is very challenging to study the process experimentally as it involves high energy beam interaction, rapid melting and rapid solidifification. Therefore, alternative strategies, such as computational modelling and simulations are an emerging area to study this process. Numerical modelling becomes an effective tool to understand the effect of numerous process parameters and to obtain optimized conditions for the SLM process.