To manufacture a protective coating with low thermal conductivity and good frictional wear performance, a Fe_(59)Cr_(12)Nb_5B_(20)Si_4 was designed and produced to prepare coating by High velocity oxygen fuel (HVOF) spraying, in comparison with commercially stain steel AISI 316L coating. Both as-deposited coatings exhibit dense layered structure with the porosity below 1% and slight oxidation. The microstructure of Fe-based coating composes of amorphous matrix and some precipitated nanocrystals, resulting in the thermal conductivity of designed Fe-based coating (2.66 W/mK) is significantly lower than that of stain steel coating 316L(5.87 W/mK). Depending on the structure advantage, the Fe-based coating exhibits higher microhardness, reaching to 1258±92 HV. The friction coefficient and wear rate of Fe-based coating display an increase at 200°C followed by a decrease at 400°C determined by the evolution of wear mechanism at different temperature. The dominant wear mechanism of Fe-based coating at room temperature is fatigue wear accompanying with oxidative wear. At 200°C, due to the existence of "third body" abrasive wear, the wear process was accelerated. The large-area oxide layer is supposedly responsible for the decrease of friction of the coating at 400°C.
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