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101.
The mechanical model was established for the Dirac-type anti-plane transient fracture problem of the weak-discontinuous interface
between two FGMs half-planes. Integral transform was adopted to derive Cauchy singular integral equation and Erdogan’s allocation
method was used to calculate transient stress intensity factors numerically. The numerical solutions of the weak-discontinuous
case were contrasted with those of the infinitesimal-discontinuous one. Two possible effective methods to diminish the peak
values of transient stress intensity factors are discussed. One is to reduce the weak-discontinuity of the interface, i.e.,
to make the ratio of the two non-homogeneity parameters be close to 1.0 and to avoid the case that the signs of the two non-homogeneity
parameters are different. Another is to make a compromise between the weak-discontinuity and the all-continuity, i.e., to
make FGMs interface infinitesimal-discontinuous. Simple method was suggested for the realization of the infinitesimal-discontinuity
of FGMs interface. From the strong-discontinuous interface to the weak- discontinuous one, and then to the infinitesimal-discontinuous
one, this is a law and trend of the development of composite interfaces. To design and manufacture infinitesimal-discontinuous
interfaces may be a brand-new effective approach to enhance the reliability of composite structures, and the first rank infinitesimal-discontinuity
is enough to improve the mechanical performances of composites notably. 相似文献
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以装甲车内电气设备检查、维护修理为应用背景,设计了一种24V/200A的充电电源设备。主电路采用双管双正激拓扑结构,采用了逐脉冲电流比较控制技术、软开关技术。通过无主均流法解决了双模块并联工作后模块间的功率均分控制问题。实验表明设备达到了预期的设计目的。 相似文献