Influence of Ni addition on Abrasive wear behaviour of plasma-sprayed Duplex stainless steel coatings

Abstract

Many austenitic and ferritic stainless steels have a higher yield and ultimate tensile strength than duplex steels. The extent to which this is true is determined not only by the alloy’s composition but also by how it is treated. This increased strength is usually accomplished without sacrificing the alloy’s hardness, as long as the alloy does not contain any of the harmful phasing elements. Thus an attempt is made to study the duplex stainless steel being plasma sprayed on a substrate and study its microstructure, hardness, and abrasive wear resistance. The primary objective is to study the abrasive wear resistance of duplex stainless steel coatings on 316 stainless steel. Ni percentage in coatings is varied at the coating stage in weight percentages of 7.0, 7.5, and 8 % and to study its effect on the wear rate of the coatings. The composition of the coatings is confirmed using XRD. A two-body abrasive wear test is carried out to determine the wear rate of the coatings with varying percentages of Ni and varying loads. Besides, the coatings are characterized by optical microscopy. Weight loss measurements of the tested samples are carried out and the data obtained is analyzed through weight loss plots. Also, weight loss data is used to further calculate the wear rate which is analyzed using wear rate plots. Finally, the microhardness of the coatings is determined.