Effect of Al and Ti additions in cast nickel base alloy, grade Hastelloy X by Arc Melting Process on Microstructures and Oxidation Behavior at 900°C and 1000°C

摘要

The nickel base alloy, grade Hastelloy X was modified by Aluminum and Titanium additions by means of vacuum arc melting process in order to improve microstructural characteristics and oxidation resistance. The arc melted Hastelloy X was added Aluminum and Titanium each for 2%, 4% and 6% by weight. Then all specimens were performed with heat treatment, which consists of solutioning treatment at 1125°C for 24 hours and precipitation aging at temperatures of 760°C, 800°C and 845°C for 24 hours. Both aluminum and titanium additions resulted in network intermetalic phase formation, namely, s-phase, throughout the matrix. Furthermore, the addition of both elements provided the better oxidation resistance for the alloys.