Study of the Microstructural Behavior of the Ti-6Al-4V Alloy in Creep Test at 600°C

The objective of this work was evaluating the microstructure of the Ti-6Al-4V alloy in creep test. Yttria stabilized zirconia with a CoNiCrAlY bond coat was atmospherically plasma sprayed on substrate. Constant load creep tests were conducted with alloy in air and in nitrogen atmospheres at stress level of 319 MPa at 600°C. The microstructural analyze shows that the predominant mechanism in the test conditions was characterized by formation and coalescence of microcavities with shape and size varieties. The size and shape of dimples are governed by number and distribution of nucleated microcavities and by stress internal level present in material.