(Ti,Mo)(C,N)-25 wt% Ni coatings obtained by spraying an agglomerated and sintered feedstock powder using different high velocity air-fuel (HVAF) and high velocity oxygen-fuel (HVOF) deposition processes are comparatively analysed for their sliding, abrasion and impact resistance. All HVOF-sprayed coatings are particularly dense, with approximate to 800 HV hardness (tested at 100 gf, 300 gf and 500 gf). In-flight oxidation resulted in some embrittlement, as revealed by scratch tests. In ball-on-disk sliding against an Al2O3 counterpart, they maintained a mild wear regime (wear rates <= 10-6 mm3/(N center dot m)) from room temperature up to 600 degrees C, with better performance in comparison to Cr3C2-NiCr reference coatings. At room temperature, the Ti(C,N) hard phase limited the abrasive cutting by counterbody asperities. At 400 degrees C and 600 degrees C, the coatings developed a thin, protective oxide tribofilm. They also exhibited no interface delamination in cyclic impact tests. However, they suffered higher wear (approximate to 3-5 x 10-3 mm3/(N center dot m)) in high-stress particle abrasion testing, particularly when compared to HVAF-sprayed Cr3C2-NiCr. Gaining improved control over inflight oxidation of (Ti,Mo)(C,N)-Ni during spraying is probably the key to overcome this limitation. The HVAF-sprayed (Ti,Mo)(C,N)-Ni coating exhibited severe interlamellar decohesion under all test conditions, as the limited melting degree of the feedstock did not compensate for the intrinsic microstructural inhomogeneity of the powder particles.
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