High-chromium iron-base composite coating prepared by reactive plasma cladding using asphalt as carbonaceous precursor

A kind of Fe-Cr-C-W-Ni composite powders for reactive plasma cladding was prepared using iron, chromium, wolframium, nickel and sucrose (to pyrolyze the sucrose as carbonaceous precursor) as raw materials. High-chromium iron-base composite coatings were synthesized on the hardened and tempered C grade steel by reactive plasma cladding. Results show that the particle of Fe-Cr-C-W-Ni composites powder for cladding is uniform without any impurity. The high-chromium iron-base composite coating by reactive plasma cladding consists of a lot of the primary reinforced phase of (Cr,Fe)7C3 which distributes on the matrix of eutectic (Cr,Fe)7C3/γ. The coating has a metallurgical bonding with hardened and the substrate of tempered C grade steel. The average microhardness of the coating is about 1 100 HV. Under the same condition of wear test, the wear volume of the high-chromium iron-base composite coating is one seventh of that of the Ni60 coating by reactive plasma cladding.