Precision Casting of Ni-Al Alloy and Simultaneous Joining to Dissimilar Metals by Modified Centrifugal Combustion Synthesis

Abstract

A modified centrifugal combustion synthesis process has been developed that enables precisely casting synthesized materials and simultaneously joining them to a dissimilar metal. The material to be synthesized was a Ni–25 mol%Al alloy; that to be bonded with the synthesized material was a stainless steel, an ultra-low carbon steel, pure nickel or a Ni–25 mol%Al alloy. The base material to be bonded; a graphite mold; and a green compact of reactants consisting of Al, Ni and NiO were set in a centrifugal caster. When the combustion synthesis reaction was induced in the centrifugal force field, synthesized molten Ni–Al alloy flew into the mold and collided with the base material. This process was successfully applied in joining the synthesized Ni–Al alloy and various base materials. Centrifugal force was also confirmed to assist the molten Ni–Al alloy fill the mold cavity and adhere to the surface of the base materials.