Ranking the Resistance of Wrought Superalloys to Strain-Age Cracking

摘要

High-strength, heat-resistant alloys are critical construction materials for modern gas turbines used in power generation and aviation applications. The use of higher-strength alloys has long been limited by the susceptibility of some of these alloys to strain-age cracking during postweld heat treatment. No widely accepted test method exists that provides an easy and economical method of ranking the resistance of alloys to strain-age cracking. Of the test methods that appear in the literature, the controlled heating rate test (CHRT), developed in the 1960s, stands out because it is simple and economical as well as having been correlated to restrained weldment test results. In this investigation, the CHRT was used to rank several commercial alloys by their re-sistance to strain-age cracking, and alloy performance was correlated to chemical composition.