A New Class of High Temperature and Corrosion Resistant Nickel‐Based Open‐Cell Foams

A number of nickel‐based and iron‐based alloys have been successfully developed for applications at high service temperatures and in corrosive environments. Applications such as diesel particulate filters, heat exchangers, and catalyst supports require open‐cell porous structures with tailored and uniform material and structural properties, a requirement which can be met by high temperature and corrosion resistant metallic alloy foams prepared with compositions similar to those mentioned above. A new technology that transforms pure nickel foam into an alloy foam, and which has now reached the pilot plant production stage, will be introduced. This technique starts from commercially‐available nickel foam, which is uniformly coated with a pre‐alloyed powder using standard powder metallurgical methods, and subsequently transformed into the desired alloy throughout the strut cross‐section in a relatively short time with a carefully controlled heat treatment that utilizes transient liquid‐phase sintering. This process allows for the preparation of a wide variety of foam compositions and structural features, which is important for tailoring material properties to a specific application.