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81.
82.
X. S. Ning K. Suganuma T. Okamoto A. Koreeda Y. Miyamoto 《Journal of Materials Science》1989,24(8):2879-2883
Two kinds of additive-free silicon nitride ceramics were brazed with aluminium; one was with as-ground faying surfaces and
the other was with faying surfaces heat-treated at 1073K for 1.8 ksec in air. The heat-treatment of the silicon nitride ceramics
formed a silicon oxynitride layer on the faying surfaces and increased the brazing strength of the joints. A silica-alumina
non-crystalline layer and a β′-sialon layer were formed successively from the aluminium side at the interface of the joints.
The heat-treatment which made the former layer thicker is a necessary process in making reliable, strong brazed joints. 相似文献
83.
Kitakami O. Ogawa Y. Fujiwara H. Kugiya F. Suzuki M. 《IEEE transactions on magnetics》1989,25(3):2607-2611
A Co-Cr film deposited directly on a substrate has an initial growth layer with low coercivity. However, the existence of a Ti underlayer prevents the formation of such a layer. As a result, Co-Cr film deposited on a Ti underlayer has high perpendicular anisotropy and coercivity even in cases of extremely thin film thickness (200 Å). As for the read-write characteristics of Co-Cr thin-film media, the existence of such an initial growth layer greatly improves the reproduced output level. The cause for this is considered to be that the free charges which appear on the back surface of the perpendicular recording layer are reduced and the demagnetization field acting on the recorded magnetization subsequently decreases due to the existence of the initial growth layer 相似文献
84.
85.
Y. Nath P. C. Dumir R. S. Bhatiaf 《International journal for numerical methods in engineering》1985,21(3):565-578
The present work investigates the efficacy and applicability of interior global orthogonal point collocation method to the axisymmetric nonlinear analysis of elastic circular plates and shallow spherical shells subjected to uniformly distributed transverse load. Spacewise discretisation has been carried out using a polynomial expansion with the zeros of a Chebyshev polynomial as collocation points. Timewise integration has been carried out with Newmark k-β scheme corresponding to average acceleration method. The static response and snap-through buckling results, as well as, the dynamic response and dynamic buckling results under a uniformly distributed step load have been obtained and found to agree closely with the available results. 相似文献
86.
C. Y. Liao S. N. Atluri 《International journal for numerical methods in engineering》1991,32(6):1339-1361
An efficient method, based on the Schwarz–Neumann alternating technique, is presented for computing weight functions of a general solid (3-D as well as 2-D), with embedded or surface-flaw configurations. The total rate of change of the crack-opening displacements, due to simple perturbations of crack-dimension characteristics, is conveniently decomposed into the infinite-domain and boundary-correction parts. The former is determined from available analytical solutions of ideal-shaped cracks, whereas the latter is computed numerically by imposing nil boundary-traction requirements for the displacement field corresponding to the weight functions. Numerical examples, with solutions for 3-D weighted-average and local stress intensity factors, indicate that the proposed method is very accurate and efficient. 相似文献
87.
Flux pinning characteristics have been investigated for the Nb x Ti100-x /Nb(x = 65, 50 and 28) and Nb 28 Ti 72/Nb 65 Ti 35 superconductor(S)/superconductor(S′) multilayers. The maximum of the pinning force F p⊥ max perpendicular to the layer plane as a function of the structure modulation length λ has a peak in the quasi-two-dimensional region (λ~20 nm). The maximum. values of the F p⊥ max versus λ curve are proportional to the difference of the GL coherence length (ξ GL ) between the superconductive sublayers S and S′. The results suggest that the large F p⊥ max in the S/S′ multilayer is caused by the repulsive pinning force due to Nb layers with larger ξ GL . 相似文献
88.
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