Metal powder plays a very important role in the additive manufacturing processes. Indeed the quality of metal powder used will have a major influence on properties but it can also influence:
- The build-to-build consistency
- The reproducibility between AM machines
- The production of defect-free components
- The manufacturing defects on surfaces
A very wide range of alloys are used on additive manufacturing machines thanks to the availability of metal powders:
- Steels: 316L, 17-4PH etc.
- Nickel and cobalt base superalloys: 625, 718, CoCr F75 etc.
- Titanium alloys: Ti6Al4V, CPTi etc.
- Aluminium alloys: AlSi10Mg etc.
But many other metals are also evaluated and developing such as Copper alloys, Magnesium alloys, Precious metals such as gold, silver, platinum, Refractory metals such as Mo alloys, W and WC, and Metal Matrix Composites, etc.
Metal powders for AM are usually produced using the gas atomisation process, where a molten metal stream is atomised thanks to a high pressure neutral gas jet into small metal droplets thus forming metal powder particles after rapid solidification. The reason why gas atomisation is the most common process for additive manufacturing is because it ensures:
- A spherical powder shape
- A good powder density, thanks to the spherical shape and particle size distribution
- A good reproducibility of particle size distribution
Some other powder manufacturing processes are used for specific alloys such as Plasma atomisation and spheroidization, centrifugal atomisation, also known as plasma rotating electrode process, and powder blending and mechanical alloying, to produce Metal Matrix Composites (MMCs).
Key metal powder characteristics for additive manufacturing can be sorted in four main categories:
- Chemical composition
- Particle size distribution (PSD)
- Physical properties
In all cases, there are several useful existing standards to determine methods for characterising metal powders. Additional points are important to consider when selecting metal powders for additive manufacturing processes:
- Storage and aging of powders
- Reusability of powder after additive manufacturing cycles
- Health, safety and environmental issues
This year’s AM seminar will be focusing on metal powders. The event will be taking place in Metz, France. The seminar will cover important aspects such as powder production and characterization, investigation of process related powder properties, specifically for AM. In addition to traditional AM processes such as LPBF and Binder Jetting, advanced materials and emerging technologies in AM will also be inspected during this important meeting of the AM ecosystem. A wide range of presentations will be given from the industry and the academia within the seminar, as well as interactive slots of interesting panel discussions on related topics of AM.
Hosted by IRT-M2P (Institut de Recherche Technologique Matériaux, Métallurgie & Procédés), the event will provide a platform for networking, presentations from key areas, and culminating in a chance to have an exclusive tour of the IRT-M2P facilities.