High Performance Ceramic-Metal Composites

Ceramic-metal composites, or cermets, are widely used in the oil and gas, chemical processing, and manufacturing industries, due to a combination of high resistance to wear and corrosion, combined with excellent toughness and damage tolerance. Two novel cermet systems will be developed and evaluated in the present study, building on the previous work of the primary applicant (Dr. Plucknett). Current cermet systems such as tungsten carbide/cobalt suffer from a number of performance limitations, notably poor corrosion resistance, severe strength degradation at elevated temperatures and high mass. The new cermet systems are based on the use of ductile nickel aluminides or stainless steels as the metallic binder phase, with titanium carbonitride and titanium carbide as the respective ceramic phases. The materials that are to be developed will be characterised in terms of their mechanical properties, together with their wear and corrosion resistance, and compared to current state of the art cermets. Composite development will be based upon the use of colloidal forming methods to produce the ceramic preforms, building on our current work in this area. Cermet densification can then be achieved by infiltration of the molten binder alloy (or melt). Colloidal forming allows techniques such as gel casting to be employed, allowing the production of complex shaped components. Subsequent green machining is then possible, prior to melt-infiltration, giving the possibility of net-shape component production. In particular, these new materials are aimed at potential application in the demanding environments of the Canadian oil and gas industry, which combines the need for both wear and corrosion resistant materials. The proposed research will support up to seven HQP at Dalhousie University, with clear potential for intellectual property development.