Superalloy Development for Aircraft Gas Turbines

Abstract

The creep resistance of nickel-base superalloys has progressed consistently over the past two decades. These improvements have been accomplished through the use of three principal strengthening mechanisms, solid solution strengthening, intermetallic (gamma prime) strengthening, and carbide strengthening. Most recently statistical regression analysis has been employed to predict the influence of alloying ingredients in nickel, and an alloy (TRW-NASA VI A) has been designed through this procedure. Superalloys, along with appropriate cooling mechanisms, appear to be entrenched as the materials of construction for the hotter portions of aircraft gas turbines for at least the next ten years.