The Effects of Crystallographic Texture on the Mechanical and Fracture Properties of Ti-3Al-2.5V Hydraulic Tubing

The effects of crystallographic texture on the mechanical and fatigue properties of titanium alloy 3Al-2.5V seamless hydraulic tubing are presented. Theoretical as well as experimental evidence has shown that burst strengths, formability, fracture toughness, and fatigue strengths are improved if a crystallographic texture is developed such that the basal planes are oriented parallel to the tube surface. This radial texture is preferentially developed when during tube fabrication the amount of wall reduction is high compared to tube diameter reduction. The various techniques that have been developed to experimentally determine the degree of texturing present in a particular tube are also outlined. Two techniques are currently being used to evaluate texturing in tubes: x-ray pole figure determinations and strain ratio measurements made from tube tensile tests.