Comparative Analysis between 5th and 6th Generation Superalloys and Previous Generation Superalloys

Abstract

In harsh working environments where there can be very high temperatures and heavy loads, like in the inside of the combustion chamber of a rocket, industrial gas turbines, space vehicles, and so on, a special class of material will be needed for making the required parts. This special class of materials is called superalloys. There are many types of superalloys based on the major alloying element. But, among these, Ni-superalloys stand out significantly due to their superior mechanical and physical characteristics. Thus, they are widely used in situations where the working conditions are unbearably harsh for ordinary materials. And, due to this, a lot of research have been done on Ni-superalloys for improving them and studying their properties. This extensive research work has led to the development of many generations of Ni-superalloys, with alloys getting better and better with each passing generation. Among all generations, the 5th and 6th generations of Ni-superalloys are the most recently developed ones. With the development of 5th and 6th gen alloys being very recent, there are not many studies conducted on them. With the current bloom in aerospace, energy, and thermonuclear research fields, the need for materials such as Ni-superalloys that can withstand absurdly harsh environments is increasing. That is one of the reasons why reviewing existing studies pertaining to recently developed new generation alloys is very important. It can help us in finding out the future possibilities for research so that we can develop new alloys or improve the existing ones. In this review paper, various aspects of these alloys such as fatigue properties, creep properties, oxidation resistance properties, corrosion resistance properties, element composition of these alloys and their impact on the above factors, use of various manufacturing methods, and the presence of additives have been extensively studied.