Selective laser melting
The process with the most control in the fabrication of metal structures using a programmable laser is termed selective laser melting or SLM. Structures are built up layer-by-layer by depositing a thin layer of metal powder, then selectively lasing to achieve the pattern needed in that section. This lasing causes a phase transition in the metal/s; the particles are completely melted for just a fraction of a second, during which they bind to the existing structure below. Only certain metals can be used including: stainless steel, tool steel, titanium, cobalt chrome and aluminium.
Direct metal laser sintering
In contrast, sintering is a process which involves spreading metal powder across a build plate. A laser applied to the powder fuses the metal particles together. In contrast to SLM, this process does not melt the metal to do so. More powder can be added to allow for cross-sectional printing. The complete object is built up through many tiny layers of fused metal particles. Unfortunately this method is very expensive.
View the DMLS process by right clicking here and select “open in a new window”.
© University of Wollongong, 2020