Wear behavior of laser cladded WC-FeAl coating on 321 stainless steel substrate

Commonly, the low wear resistance of stainless steels damages them during usage; in order to enhance wear properties, various types of tungsten-carbide-based coatings, such as WC-Co and WC-Ni, could be applied on the steel surface. To improve the mechanical properties of the coatings, instead of nickel- or cobalt-bearing coatings, WC-FeAl composite coating is used. Following the previous studies on laser cladding of the WC-FeAl composite powder on 321 stainless steel, the mechanical properties and wear characteristics of the coats are discussed here. Mechanical evaluations showed that hardness, fracture toughness, and the modulus of elasticity of the coating were, respectively, 1600 HV, 5.7 MPa m1/2, and 355 GPa. Moreover, a wear test was conducted at ambient temperature with a 30 N load for 3000 m. The results indicated that by applying the coating, the weight loss of the 321 steel decreased from 146 to 0.7 mg. Besides, the wear rate of the coated sample was 0.57 mm3/N m. Further analysis conducted on the worn surfaces of the coated samples depicted that parallel scratches formed on the surface, indicating that the abrasion wear was the main mechanism for WC-FeAl coating.