Creep Crack Growth Test Method and Creep Crack Growth Properties for TiAl Intermetallic Compound
Abstract:VAMAS project which aims to establish the standard test method of creep crack growth for creep brittle advanced materials is being conducted. The round robin tests on TiAl intermetallic compound with fully lamellar structure were carried out. Based on the results of round robin, the recommended test method was proposed. Fatigue precracking was not applicable to this material as a standard method because fatigue crack deviated along the lamellar structure. In the present study, the machined V-notch specimen was recommended based on the experimental results and stress distribution analysis ahead of the V-notch. Creep crack growth properties and creep fracture mechanism of the present TiAl were clarified. Creep crack growth properties depending on test temperatures were also investigated in terms of the creep fracture mechanism for this material. Key Words:Creep crack growth, TiAl intermetallic compound, Fully lamellar structure, Standard test method, V-notched specimen, Creep fracture mechanism