Fatigue Behavior of Weld Titanium Alloy Hydraulic Tube

摘要

Titanium alloy hydraulic tubes were weld with gas tungsten arc welding method in this work. The microstructure of weld zone and heat affected zone are clarified with metallographic microscope, And followed by tensile test and fatigue test, with stress rate R is 0.1 and frequent is 10 Hz. It is found that, the microstructure in weld zone is coarse and uniform β grains about 1.5 mm and paralleled acicular martensite α phase. Mechanical test shows that cracks initiate at inner circle of pipeline and spread alone circle line promptly throughout the whole inner circle. Cracks initiation side appreance a clusters of slip bands, those may alone the coarse and laminated acicular martensite α phase in weld zone and heat affected zone.