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Many parts in steel industry commonly failed due to being subjected to the abrasion and corrosion conditions even with mechanical impact or high temperature atmosphere,which requires efficient surface-protection coating deposited on the parts in order to avoid costly downtime and to reduce costs for expensive spare parts.In past literature,many hardfacing techniques such as build-up welding,thermal spraying and laser cladding have been widely used for above demands.This paper introduces a new coating process plasma transferred arc ( PTA) weld- surfacing with some specials : larger selection range of coating component and depositing composite coating like Nickel-based or Cobalt-based cermet due to using powder feedstock compared to conventional build-up welding technique,lower production cost,higher productivity and thicker coating layer while compared to laser cladding layers,in addition to superior coating-substrate interface to thermal spraying coating.In this paper,a Nickel-based PTA overlay reinforced with 60 wt% of tungsten carbides ( WC) was produced to enhance the surface properties of DRI screw and DRI distributor in Baosteel COREX blast furnace.Microstructure observation from optical microscopy and scanning electronic microscopy ( SEM) indicate that the WC particles which mostly maintain original shape and exhibit few dissolution,distribute uniformly across the section of the layer.The microhardness of the Ni-based matrix is about 580 ~ 650 HV0.45.The wear tests under high temperature of 600℃ show that the Ni- based alloy reinforced with 60 wt% of WC particles exhibits good wear-resistance performance,which is attributed to the inherent high hardness and high volume fraction as well as uniform distribution of the primary tungsten carbides within the Ni-based matrix.