13th International Conference on Fracture June 16–21, 2013, Beijing, China -2- With the SLS process it is possible to melt materials like bronze [6]. Materials with a high melting point can be mixed with a lower melting point material in order to form a composite of, for instance, bronze as a matrix with embedded particles of steel or nickel [6]. With the SLM process, near net shape components can be manufactured directly from a CAD model. The model is sliced into thin (max 100µm thick) layers. Powder is spread onto a metallic build platform and the powder is fused in layers with a laser as dictated by the CAD model. The laser energy is intense enough to permit full melting (welding) of the particles to form solid metal. The process is repeated layer by layer until the part is complete. Examples of metallic materials commercially available for the SLM process are stainless steels AISI 304L [7] and 316L [8, 9], Aluminium alloys [10], Titanium Ti6Al4V [4] and also more temperature resistant materials such as Inconel 625 [4]. The laser melting manufacturing process can, as mentioned, be described as a layer-by layer process, where powder is distributed on a powder bed, Figure 1. After powder distribution, the powder is melted and a metal slice is formed on the powder bed. a) b) c) d) e) f) I II III Figure 1. Schematic description of the SLM process. a) Powder is distributed on a powder bed, the build platform. b) The powder is melted by a laser beam and a slice of solid metal is formed. c) The powder bed is lowered and the process is repeated until a finished component is formed. I: A powder distributer travels over the powder bed cavity contained by the build chamber walls b) and build plate c). Molten and solidified powder constitutes the component d) surrounded by unmolten powder e). II: A laser beam f) melts the powder layer and creates a new slice of solid material in the component d). III: A ram lowers the build platform c) and the process is repeated until
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