Microstructure and crack sensitivity of electron beam welded titanium aluminide joints

作者：Wu HQ; Feng JC^*; He P; He JS

来源：Transactions of Nonferrous Metals Society of China, 2005, 15: 1-4.

• crack
• titanium aluminide
• electron beam welding
• microstructure

Microstructural characterization and crack formed mechanism during electron beam welding of titanium aluminide Ti-45Al-1. 7Cr-1. 7Nb were investigated. The results show that the welded microstructure exhibits columnar and dendritic structure. Microstructural constituents in the fusion zone are a massive gamma structure and some lamellar structure consists of alternating platelets of alpha(2) and gamma. The major contributing factor of the susceptibility to solidstate cracking is thermally induced stress. The import role of the suppression of the a phase decomposition, the difference of alpha(2)/gamma phases thermal expansion coefficient and the lamellar spacing changes of lamellar structure with cooling rate all play effect on the crack forming mechanism.

• 出版日期2005-4
• 单位哈尔滨工业大学