Boriding of Ni40Al

Abstract

Boriding has been one of the thermochemical processes that have been developed and used recently in industries. The main advantages of this technique are leading to the high strength of abrasion wear and high oxidation resistance compared with other conventional surface treatments Ni-Al alloy is a new material that offers improved high-temperature properties over traditional ferrous and nickel based hot work die materials. In this study, Ni and Ni-40Al alloys were borided. Ni40Al at. % alloy was prepared by vacuum arc melting under argon atmosphere. Boriding of Ni and Ni-Al alloys was carried out with Ekabor–Ni powders at 875 C for 2, 4, and 6 h. The characterization of the boride layer formed on the surface of nickel aluminide substrates was identified by optical microscopy. Microhardness and thickness of boride layers were measured. Its hardness was found to be higher than the cast Ni-40Al alloy. The thickness and of boriding layers were found to be different depending on the boriding time.