Combination of electroforming and cold gas dynamic spray for fabrication of rotational moulds: feasibility study

Abstract

Actual trend in Additive Manufacturing is producing of multimaterial objects. For example, in the case of fabrication of rotational moulds, the multilayer concept with combination of nickel and copper as primary materials for shells seems to be promising. In this work, hybrid approach combining the advantages of electroforming process (accuracy, reproducibility, and quality of material) and cold spray (small amount of heat transferred to the substrate, retention of microstructure, and properties of feedstock and fast speed of process) for producing of multimaterial mould is discussed. Experimental results of the feasibility study presented in this paper show that cold spray deposition of thick (2–4 mm) copper layers on nickel substrate produced by electroforming technique is possible if an intermediate copper layer produced by electroplating is applied. Addition of ceramic particles to the copper feedstock powder permits to perform cold spray deposition directly on electroformed nickel surface without intermediate layer, but bonding strength in this case is lower. Thermal shock tests did not reveal any evidence of layers delaminating in both cases.