Development of metal matrix composite materials for wear resistant coatings using a laser rapid-alloy-prototyping technique

A rapid-alloy-prototyping technique based on variable powder feed rate laser cladding was used to develop a new class of metallic matrix composite materials (MMC) for abrasive wear resistant coatings. The development of the materials was performed in two steps. In the first step, the composition of the matrix was optimised by producing coatings with variable compositions, lying in the Fe-rich comer of the Fe-Cr-C system. In the second step, the influence of the volume fraction of reinforcement particles on the wear behaviour of the composite was studied by testing composites formed of a matrix with optimised composition and variable proportions of NbC. The wear behaviour of the composite coatings was evaluated by three-body abrasive an dry sliding micro-scale wear tests. The methodology for alloy design and the optimisation of the constitution of the composites are presented and discussed.