Advances in powder bed based Additive Manufacturing of metal-glass-hybrid-components

Abstract

As powder bed based additive manufacturing (AM) is gaining more traction in the research and industry, significant efforts are made to expand the capability of AM in combining different materials. Conventionally, multiple materials, sealants and processes are necessary in order to join metal and glasses in assemblies. The development of a single-step process for vacuum-tight and strong bonding between glass and metal could drastically reduce the part count and assembly cost. This paper investigates the feasibility of joining the iron-nickel-cobalt alloy Kovar with borosilicate glass. The powder bed fusion by laser beam is used to melt Kovar structures directly onto glass substrates. Suitable process parameter for an iron-silicon-oxide material-bonding layer of 3 µm thickness were developed using design of experiments. With an energy input of 333 J/mm3 for the initial layer and 60 J/mm3 for the bulk structure, tensile testing of the metal-glass-connection revealed bonding forces up to 0.5 MPa.