Typically, highly wear resistant PTA materials for mining and mineral processing applications are developed byadding ceramics like tungsten carbide to appropriate matrices. The problem is that failure during abrasion canoften occur as a result of preferential wearing of the soft matrix material or crack formation through the highlyloaded brittle ceramic phases. In this paper, the development of new highly wear resistant plasma transferred arc(PTAW) iron based alloys will be detailed. In this case, the matrix material itself was found to have excellentabrasion resistance with high hardness obtained in the weld deposits up to Rc 66 from the development of a finestructure consisting of a high volume fraction of complex M23(BC)6 and M7(CB)3 borocarbides phases. Thematrix material is found to additionally exhibit high toughness up to 73.3 MPam1/2 due to an effective distributionof fine carbide and boride phases in a ductile dendrites / cells. When adding WC particles to the starting powderand welding, the matrix was found to effectively wet the WC particles forming a strong tough matrix which avoidsthe typical "pull-out" or cracking found in conventional PTAW hardfacing materials. Specific weight lossmeasurements were conducted using ASTM G-65 wear testing and will be correlated to the structure achievedduring PTAW.
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