Fabrication of a bimetal by combining casting and additive manufacturing

Purpose and goal:

The Combi-CAM project aims to develop a completely new manufacturing route for fabrication of a bimetal. The focus of this project is framed around the laser powder bed processing (PBF-LB) of the nickel-based superalloys IN718 on top of a cast H282 part. The aim is to generate novel knowledge of how the microstructure, mechanical properties and productivity are affected by using a hybrid manufacturing route combining laser powder bed fusion and conventional casting.

Expected results and effects:

The methodology proposed in COMBICAM project has led to increase the partners understanding and knowledge on how to produce a bimetal made of IN718 and H282 by combining PBF-LB and casting. Optimization of PBF-LB process parameters and HIP treatment, led to develop a strong bonding between two dissimilar materials, fulfilling aeronautic requirements in term of defects mapping. The project also contributed to gain in knowledge on how to set up the PBF-LB for printing on existing parts.

Approach and implementation:

The project provided detailed information on the microstructure and integrity of the binding zone, and results were compared to reference samples for each base material. The information was crucial to understand the material-process-property relationship when fabricating bimetals. The samples were evaluated both as-produced and after post treatments. Demonstrators disclosed and confirmed the hybrid manufacturing concept, i.e. combining PBF-LB and casting, as suitable for further investigations.