摘要:

A computer‐simulated model for the fatigue behavior of multifilamentary unidirectional composites is presented. It is applicable to two‐component composites with perfectly elastic filaments in a ductile matrix, and considers both applied cyclic stresses and strains. Information regarding the change in residual stress state, matrix yield strength, and the number of cycles necessary to stabilize properties by the achievement of totally elastic strains (shakedown), or to reach some preassigned failure stress in the matrix, can be determined. Results obtained are applied directly to the fatigue behavior of multifilamentary Nb3Sn superconducting composites.

ISSN:0003-6951    

DOI:10.1063/1.90993

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The critical currents of superconducting A15 Nb–Ge and Nb–Ge–Si compounds prepared by CVD have been measured in applied fields up to 18 T. Current densities greater than 105A cm−2were obtained at 18 T. These results are discussed with regard to the microstructure of the films which were examined by transmission electron microscopy.

ISSN:0003-6951    

DOI:10.1063/1.90994

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

In this letter, we present a theory of interferometer resonance. This theory consists of solving the interferometer equations in the sinusoidal approximation. An expression for the resonance amplitude is obtained which is valid for allQvalues and gives perfect agreement with computer simulations. The implications of these results for SFQ memory cells are also discussed.

ISSN:0003-6951    

DOI:10.1063/1.90995

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

High‐resolution electron‐beam lithographic techniques have been used in the fabrication of thin ultranarrow superconducting Nb stripes. The ac Josephson effect in the form of microwave‐induced current steps has been observed in a series of samples in which the length has been varied from about 1 to 0.1 &mgr;m. Studies of the phase slip centers in these samples have led to an estimate for the quasiparticle diffusion length and inelastic scattering time of about 90 nm and 13 ps, respectively.

ISSN:0003-6951    

DOI:10.1063/1.91003

出版商:AIP    

年代:1979

数据来源: AIP

摘要:

The effect of a magnetic field on any crystalline material is to introduce an anisotropy in the electric resistivity. This letter examines the anisotropy which appears in the (001) plane of cubic crystals. Compact formulas are developed which show that in general the extreme values of the resistivity occur in directions which differ from those of the crystallographic axes. We thus demonstrate the existence of magnetoresistance skewness, as defined in recent papers of Allgaieretal., but have analyzed the phenomenon from a point of view which is complementary to that employed in the earlier work.

ISSN:0003-6951    

DOI:10.1063/1.91004

出版商:AIP    

年代:1979

数据来源: AIP