Selective Laser melting (SLM), also known as laser fusion welding, is a highly promising additive manufacturing technology for metals that uses high energy laser light to irradiate and completely melt metal powders to form 3D shapes.
The metal material used in SLM is a mixture of treated and low melting point metal or molecular material, during processing the low melting point material melts but the high melting point metal powder does not. The molten material is used for bonding, so the solids are porous and have poor mechanical properties, and have to be remelted at high temperatures before they can be used.
The whole process of SLM printing begins with slicing 3D CAD data, converting the 3D data into a number of 2D data layers, usually between 20m and 100pm in thickness. 3DCAD data is typically formatted as STL files, which are also commonly used in other layered 3D printing technologies. The CAD data is imported into the slicing software and various property parameters are set, as well as some control parameters for printing. SLM starts the printing process by printing a thin, uniform layer on the substrate, which is then moved through the Z-axis to print the 3D shape.
The entire printing process is carried out in a closed container filled with an inert gas, argon or nitrogen, to reduce the oxygen content to 0.05%. SLM works by controlling the vibrator to achieve laser irradiation of tiling powder, heating the metal until it is completely melted, each level of irradiation work table moves down, tiling mechanism is carried out again, and then the laser completes the irradiation of the next layer, so that the new layer of powder is melted and bonded together with the previous layer, repeating the cycle to complete the 3D geometry. The workspace is usually filled with inert gas to avoid oxidation of the metal powder and some have air circulation systems to eliminate sparks from the laser.
SLM printed parts are characterized by high density and high strength. The SLM printing process is very high-energy, and each layer of metal powder must be heated to the melting point of the metal. The high temperature cause residual stress inside the SLM final printed material, which can affect the mechanical properties of the part.
JS Additive’s metal printers are supplied by well-known domestic manufacturers, and its 3D metal printing services have expanded to overseas markets worldwide, where the quality and delivery times are well recognized by overseas customers, especially in Europe, America, Japan, Italy, Spain and South East Asia. 3D metal printing services are mostly used to help traditional enterprises change the way they produce, saving time and the cost of the product itself, especially in the current harsh environment of the epidemic.
