C/SiC复合材料螺栓螺牙承载能力

为了对C/SiC复合材料螺栓螺牙的承载能力进行评估,采用有限元法和刚度折减方法对C/SiC复合材料螺牙抵抗拉脱的能力进行了研究。结果表明:当齿合螺牙数大于6时,再增加齿合螺牙数已不能有效地提高螺牙的初始拉脱载荷;增大螺距会降低螺牙初始拉脱强度,因而也不能显著地提高螺牙的初始拉脱载荷;在螺距与螺栓直径之比保持常数的情况下,螺牙的初始拉脱载荷与螺栓直径的平方成正比;而螺牙的极限拉脱载荷则近似正比于齿合螺牙数、螺距及螺栓直径。

Load bearing capability of thread teeth of C/SiC composite bolts

In order to evaluate the load bearing capability of thread teeth of C/SiC composite bolts, finite element method and stiffness degradation method were used to study the load bearing capability of the thread teeth of C/SiC composite bolts. The results show that when the number of teeth engaged is more than six, the initial pull-off load of thread teeth almost does not increase with the number of teeth engaged increasing, and it also can not be increased significantly by solely increasing the pitch of thread for this will decrease the initial pull-off strength of thread teeth; when the ratio of thread teeth to bolt diameter is constant, the initial pull-off load of thread teeth is proportional to the square of bolt diameter; however, the ultimate pull-off load of the thread teeth is nearly proportional to the number of teeth engaged, the pitch of thread and bolt diameter.