Effects of loads on friction–wear properties of HVOF sprayed FeCrBSi coating at elevated temperatures

Abstract

A FeCrBSi coating was fabricated on H13 hot work mould steel using a high velocity oxygen fuel (HVOF) spraying. The morphologies, chemical compositions and phases of obtained coating were analyzed using a scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and x–ray diffraction (XRD), respectively, and the effects of wear loads on the friction–wear performances of FeCrBSi coating at 500 °C were investigated using a ball–on–disc wear tester. The results show that the FeCrBSi coating with the hardness of 641 HV is composed of α(Fe, Cr) solid solution phase, its bonding strength of 70.35 N is characterized with the scratch test. The average coefficients of friction (COFs) of FeCrBSi coating under the wear loads of 1, 3 and 5 N are 0.78, 0.53, and 0.42, respectively; and the corresponding wear rates are 6.41 × 10−3, 2.90 × 10–3, and 9.26 × 10–3 μm3 · N–1 · m–1, respectively. The wear mechanism of FeCrBSi coating is abrasion wear and oxidation wear, accompanied by abrasion wear under the load of 5 N, showing that the wear degree is deteriorated with the increase of loads.