Laser Metal Deposition (LMD), also commonly known as direct metal laser deposition (DMLD), direct laser deposition (DLD) and direct metal deposition (DMD), uses laser to create melt pool at the metal surface during which metal or ceramic powder is delivered via a nozzle into the melt pool to build up a 3D geometry.
Selective Laser Melting (SLM) uses a powder bed approach which focussed beam is selectively fuses powdered material, pre-placed in the build platform, by scanning cross-sections generated from a 3D CAD model of the part on the surface of a powder bed.
The aerospace industry is continually trying to make near net shape parts to reduce post process machining and LAM offers a solution to this issue. Technical challenges include control of wall thickness, control of surface finish and general part accuracy.
TWI offers two advanced additive manufacturing technologies for repair, build and rapid prototyping. They are Laser Metal Deposition (LMD) and Selective Laser Melting (SLM). TWI is also active in the UK Additive Manufacturing network.
TWI worked closely with Rolls-Royce to manufacture nickel alloy seal segments for the Intermediate Pressure stage of a Trent engine. This involved TWI taking the technology from a laboratory stage (TRL 3) through process development to successful engine testing (TRL 6/7).
TWI is at the core of collaborative research and development in this area, working in several projects with a total value of over £10 million. It has also worked on several confidential customer projects, making near net shape parts.
For more information, please email contactus@twi.co.uk.