Two new powdered metals for the rapid manufacture of nickel alloy and aluminium alloy components by additive layer manufacturing have been introduced by EOS for use in its EOSINT M 270 laser-sintering systems.

EOS NickelAlloy IN718 is a nickel-based, heat resistant superalloy which corresponds to Inconel 718. It is a precipitation hardening, nickel chromium alloy characterised by good tensile, fatigue, creep and rupture strengths at temperatures up to 700°C. It shows outstanding corrosion resistance, is ideal for many high temperature applications, and possesses excellent cryogenic properties.

The material will be of particular interest to the aerospace industry due to its demanding requirements. EOS has already carried out extensive tests in collaboration with several pilot customers. It has developed process parameters that enable good part building and ensure that the relevant industrial standards for this material type can be reliably fulfilled. These include, for example, heat treatment in accordance with AMS 5662 and AMS 5664 standards, as well as tensile and stress rupture properties at elevated temperature (650°C).

Greg Morris, President of pilot user Morris Technologies Inc in the US, said, "We have been supplying parts in EOS CobaltChrome MP1 as a preferred material for high stress / high temperature environments since 2005.

“Since working with EOS NickelAlloy IN718, this has become our front-line material of choice for many applications in aerospace and other demanding applications. The material allows us to produce parts that will see some of the most demanding environments including high temperatures, high stress loads and extended fatigue situations.

“Not only has the sintered nickel alloy performed well in such tests and environments, but Morris Technologies’ material characterisation efforts have also demonstrated that it performs to ASTM standards."

Ian Halliday, CEO of pilot user 3T RPD in Newbury, UK, added, “EOS NickelAlloy IN718 has helped to open up new application areas for us. We are working with some of our customers to qualify this material for future series production of aerospace components.

“Tests have shown that the mechanical properties of parts built from the material exceed what our customers are used to from cast parts. They also report that the components are easier to machine than conventional Inconel 718.”

EOS Aluminium AlSi10Mg powder, a typical casting alloy, is the first aluminium-based powder to be qualified for EOSINT M 270 systems and opens up new application areas due to its light weight and excellent thermal conductivity. Thorough process development and testing were performed as preparation for the launch.

Cast parts in conventional AlSi10Mg are typically subjected to T6 heat treatment, including solution annealing and quenching followed by age hardening at elevated temperatures.

Mike Shellabear, Vice President M Technology, commented, “Due to the rapid melting and resolidification caused by exposure to the lasers, the sintered parts match or even exceed conventional heat-treated parts in the as-built condition. So even more time and cost can be saved in the process chain.”

EOS has already produced examples of laser-sintered aluminium alloy components illustrating intelligent designs such as hollow parts and mesh-like structures with high stiffness-to-weight ratios. The material is expected to open up new markets in the area of light alloys.

Dr. Hans Langer, CEO and founder of EOS, stressed, “Developing new materials for laser-sintering at the request of and in close cooperation with our customers continually pushes our technology to the next level.

“Application-led creation of the latest two powders — EOS NickelAlloy IN718 and EOS Aluminium AlSi10Mg — are good examples and highlight the design possibilities that e-Manufacturing can offer to improve the performance of users’ products."