A STUDY OF THE NATURE OF THE DUCTILE-BRITTLE TRANSITION IN BETA-TITANIUM ALLOYS

This study investigates the nature of the ductile-brittle transition in beta-titanium alloys, specifically analyzing the fractographic characteristics accompanying this transition under varying temperature conditions. The objective of the research is to elucidate the relationship between fracture surface topology and temperature, aiming to enhance the understanding of brittle fracture mechanisms in these materials. The methodology involved preparing a beta-titanium alloy subjected to solid solution treatment and performing static bend tests at low temperatures, notably at -180°C. Detailed fractographic analysis was employed using microsections and various microscopy techniques, including a binocular microscope and electron microscopy, to observe the fracture surfaces and determine facet orientations. Results indicated that at -180°C, the fracture surfaces exhibited facets without any fibrous structures, highlighting a clear ductile-brittle transition. This investigation not only provides insights into the evaluation of metal quality through fractographic appearance but also contributes to understanding the low-temperature brittle fracture behaviors of beta-titanium alloys.