Ivasyshyn A. Increasing of high temperature and corrosive fatigue crack growth resistance of Ti-Si-Al-Zr alloys

Moulden Ti-Si-Al-Zr alloys and their characteristics of the fatigue fracture resistance at high temperatures and corrosion environment. To determine the structural and metallurgical aspects of Ti-Si-Al-Zr alloys strength and fatigue crack growth resistance increase based on the results of the investigation of their fatigue fracture processes at high temperatures and in corrosion environment. Methodological base of the study is an optical and raster electron microscopy, X-ray and fractography analyses, electrochemical investigation and mechanical tests of the crack growth resistance at cyclic loading and strength at static loading. Regularity of the influence of Ti-Si-Al-Zr alloys structure in cast, heat treated and termodeformed conditions on the characteristics of fatigue crack growth resistance at high temperature and in corrosion environment was determined. Usage of small specimens for obtaining an accurate value of fatigue crack growth resistance characteristics was experimentally validated. For optimization of the chemical composition and manufacturing methods of Ti-Si-Al-Zr alloys results of the investigation were used.