If you’re new to the 3D printing revolution or unfamiliar with the sintering process, a brief definition of ‘sintering’ is in order first. Sintering is an additive manufacturing process whereby a solid or porous structure is created from heating and compressing a powdered material. Laser sintering, as the term suggests, uses a laser to sinter the material. With this technique, a laser is aimed at points defined by a 3D model, and used to heat and bind powdered material. This causes the material to coalesce and create a single structure.
There are essentially two types of laser sintering processes: selective laser sintering (SLS) and direct metal laser sintering (DMLS) (note: these processes should be differentiated from direct laser metal melting and direct metal selective laser melting). The primary difference between SLS and DMLS is that DMLS refers to the sintering of metal alloys and SLS refers to the sintering of plastics, glass and ceramics. 3D printing and laser sintering revolutionized the jewelry industry because designs can now be 3D printed as wax models and then cast in the metal alloy of choice, which reduces cost and speeds up production as well as opens avenues for greater creativity.
Now, however, there is breakthrough in the sintering process itself. The breakthrough comes in the new ability to 3D print precious metals so that prototype parts and end products can be printed directly. This isn’t actually due to an improvement in additive manufacturing technology, though. Rather, the breakthrough is a result of an improvement in the quality of precious metal powders and new laser melting machines that are smaller than earlier models that can better accommodate the precision required in jewelry making.
While experts in the jewelry industry don’t see this new sintering capability as completely replacing the lost-wax casting process, it does nonetheless represent an exciting development in jewelry manufacturing and will no doubt catch on rapidly as the next step in 3D jewelry design.