Processing of Fe-Based Alloys by Detonation Spraying and Spark Plasma Sintering

This work deals with iron-based amorphous alloys in the form of coatings and sintered materials. It compares the structure and properties of Fe-Cr-Nb-B alloys (Fe66Cr10Nb5B19 and Fe62Cr10Nb12B16) produced by detonation spraying and spark plasma sintering. The Fe66Cr10Nb5B19 alloy has a higher glass-forming ability than Fe62Cr10Nb12B16 and the gas-atomized Fe66Cr10Nb5B19 feedstock powder was mainly amorphous, while the Fe62Cr10Nb12B16 powder with the same particle size range was fully crystalline. Detonation spraying made it possible to produce coatings with an amorphous phase as the main phase with both powders. The microhardness of the Fe66Cr10Nb5B19 coatings was lower than that of the Fe66Cr10Nb5B19 sintered alloy, at the same level of porosity (< 1%). The wear resistance of the Fe66Cr10Nb5B19 coatings was higher than that of the sintered Fe66Cr10Nb5B19 alloy. Fe66Cr10Nb5B19 and Fe62Cr10Nb12B16 coatings showed close values of microhardness and wear resistance under dry linearly reciprocating conditions. Notably, the wear resistance of the coatings was higher than that of stainless steel. This work demonstrated that detonation spraying is suitable for manufacturing amorphous phase-based alloy coatings, even for compositions with moderate glass-forming ability.