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941.
The effects of a thermal residual stress field on fatigue crack growth in a silicon carbide particle-reinforced aluminum alloy have been measured. Stress fields were introduced into plates of material by means of a quench from a solution heat-treatment temperature. Measurements using neutron diffraction have shown that this introduces an approximately parabolic stress field into the plates, varying from compressive at the surfaces to tensile in the center. Long fatigue cracks were grown in specimens cut from as-quenched plates and in specimens which were given a stress-relieving overaging heat treatment prior to testing. Crack closure levels for these cracks were determined as a function of the position of the crack tip in the residual stress field, and these are shown to differ between as-quenched and stress-relieved samples. By monitoring the compliance of the specimens during fatigue cycling, the degree to which the residual stresses close the crack has been evaluated. formerly Research Student, Department of Materials Science and Metallurgy, University of Cambridge formerly Lecturer, Department of Materials Science and Metallurgy, University of Cambridge This article is based on a presentation made in the symposium entitled “Creep and Fatigue in Metal Matrix Composites” at the 1994 TMS/ASM Spring meeting, held February 28–March 3, 1994, in San Francisco, California, under the auspices of the Joint TMS-SMD/ASM-MSD Composite Materials Committee.  相似文献   
942.
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 10, pp. 21–22, October, 1992.  相似文献   
943.
944.
945.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 3, pp. 5–8, March, 1995.  相似文献   
946.
All-Union Scientific-Research Institute of Pipes (VNITI). Il'ich Zhdanov Metallurgical Combine. Translated from Metallurg, No. 9, pp. 39–40, September, 1988.  相似文献   
947.
The authors report on a flexible system that provides visual feedback to VLSI designers with a novel display method. The basic problem is to display simultaneously two or more functions f 1, f2, . . ., each of which depends on the two spatial variables x and y. The method is based on results from visual perception experiments, which indicated that the human visual system can view simultaneously two or more images that are separated in depth, even if they are combined (superimposed) over a common spatial domain. Two display modes have been implemented: a gray-level mode and a contour mode in which only the edges separating adjacent regions are displayed in an effort to make things easier for the user. This depth-separation technique allows the viewer to register spatially the x,y distribution of multiple variables in an animation sequence. The technique can be applied to many other situations in which a single-plane episode involves several variables  相似文献   
948.
949.
A flow model and an integral method of calculating the initial length of a circular jet in a cross stream are proposed. The results of calculating the characteristics of the initial length are in satisfactory agreement with the experimental data.Translated from Inzhenerno-Fizieheskii Zhurnal, Vol. 54, No. 6, pp. 905–912, June, 1988.  相似文献   
950.
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