Haynes 282 is a relatively new precipitation hardening nickel-based superalloy which is mainly used in the hot sections of aero engines and gas turbines. This alloy has many advantages over other nickel-based superalloys owing to its superior mechanical properties at high temperature. Its excellent mechanical properties and corrosion resistance are due to the coherent γ', and its reaction with matrix combined with other phases such as carbides.

The main objective of this thesis is to increase understanding of high temperature properties and microstructure of Haynes 282 alloy. In this regard in-situ hot stage tensile test scanning electron microscopy (SEM) was performed at 920 0C. Also, many phenomena such as gamma prime precipitates coarsening, and secondary carbide formation were observed at this temperature.

Results showed that secondary precipitates of gamma prime were coarsened during the high temperature tensile test. Carbide formation at grain boundaries were also observed. Different fracture phenomena were seen where intergranular fracture was the predominant fracture mode. Some other fracture phenomena such as transgranular fracture, fracture on twinning, carbide fracture and shearing were also observed.