An evaluation of the damage tolerance characteristics of Ti-6Al-2Sn-2Zr-2Mo-2Cr sheet

摘要

A rolling practice the produce Ti-6Al-2Sn-2Zr-2Mo-2Cr sheet materials for conventional and superplastically formed airframe structure has been developed. The work described here characterizes the properties, microstructure, and fracture behavior or Ti-6-2-2-2-2 solution treated and aged (STA) sheet samples subjected to tensile and cyclic loadings. Tensile and fatigue crack growth tests were performed at ambient and elevated temperatures. The test data indicates that the crack growth behavior of Ti-6-2-2-2-2 is superior to Ti-6Al-4V sheet inthe Paris regime under comparable test conditions. Selected fractured test specimens were examined by scanning electron microscopy (SEM) to provide insight regarding fracture mechanisms under tensile as well as cyclic loading conditions.