材料期刊网

对TB8钛合金螺栓分别进行双剪切试验和疲劳试验,发现螺栓提前断裂.结合试验件断口分析、金相组织分析、X射线衍射(XRD)分析、能谱(EDS)分析和硬度检测等手段,确定了TB8钛合金螺栓的断裂模式,分析了螺栓试验件未达到试验要求的原因.结果表明,双剪切试样断口为等轴韧窝和沿晶断裂混合形貌;双剪切试样未达到试验要求可能与局部晶界及附近晶粒上析出的颗粒状脆性Ti3Al相有关;疲劳试样断口可见疲劳条带,为疲劳断裂,疲劳试样未达到试验要求可能与在β相晶粒上析出的α相的形态差异以及组织均匀性有关.

Double shear test and fatigue test were carried out to investigate the TB8 titanium alloy screws advanced broken The fracture mode of TB8 titanium alloy screws were determined and the reasons for the failure of the bolt test piece were analyzed the fracture analysis, metallographic analysis, X ray diffraction (XRD) analysis, energy spectrum analysis (EDS analysis) research and hardness testing. The results show that the fracture surface of the double shear specimen is an equiaxed dimple and a mixed fracture along the grain boundary, and the double shear specimen is not related to the test results, which may be related to the grain brittle Ti3Al phase precipitated on the grain boundary and near the grain boundaries. The fatigue specimen can be seen as fatigue fracture, which is related to the difference of the alpha phase and the homogeneity of the structure.