Selective Laser Powder Sintering (SLS) Process

- Oct 26, 2018-

The SLS process is called selective laser sintering and was developed in 1989 by C.R. Dechard of the University of Texas at Austin. The SLS process is formed from a powdered material. The principle is to spread the material powder on the upper surface of the formed part and flatten it. The high-strength CO2 laser is used to scan the cross-section of the part on the freshly laid layer. The material powder is sintered under high-intensity laser irradiation. Together, the section of the part is obtained and connected to the formed part below. When a section of the section is sintered, a new layer of material powder is applied to selectively sinter the lower section. After the sintering is completed, the excess powder is removed, and then polished, dried, and the like to obtain a part.


Advantage:

(1) High precision. The precision of the workpiece in the X and y directions can reach ±0.1~0.2mm, and the accuracy in the Z direction can reach ±0.2~0.3mm;

(2) There is no need to design and manufacture support in the manufacturing of the entity, so the production efficiency is high, the speed is fast, and the cost is low.


Disadvantages:

(1) In particular, the tensile strength and elasticity of thin-walled parts are not good enough;

(2) It is easy to absorb moisture and expand the surface moisture treatment as soon as possible after molding;

(3) The surface of the workpiece has a stepped pattern whose height is equal to the thickness of the material (usually about 0.1 mm).