Optimization of solution temperature and time in nickel-based super-alloy of engine turbo-charger based on hardness by design of experiments

Nowadays, one of important parts in combustion engines is the turbo-charger, which could improve the performance. Such this component and especially blades of the turbine, is working at high temperatures. Based on this condition and according to centrifugal forces in blades, one of design parameters is the creep strength of the material. For such condition, nickel-base super-alloy has been utilized. In this article, the hardness of 713C nickel-base super-alloy (which has been used in turbine blades of engines) increased by a typical heat treatment. For this objective, the design of experiments was utilized and the hardness through parallel and vertical lines to the grains direction in the material micro-structure was measured at different values of the solution temperature and time in the heat treatment. Experimental results showed that optimum values for the solution temperature and time are generally 1200˚C and 60 min, respectively, when the hardness increased. The sensitivity analysis indicated that effects of the temperature parameter are more significant in comparison to other parameters.