Photoluminescence of Gallate Glass-Ceramics: Al2O3 Influence

Glass and Ceramics - The influence of Al2O3 as an additive and the heat-treatment regime on the luminescence spectra of gallate glass-ceramics was investigated. It is shown that its luminescence...     

Construction of Programmed Motions of Constrained Mechanical Systems Using Third-Order Polynomials

Journal of Computer and Systems Sciences International - A problem of the synthesis of programmed motions of mechanical systems based on the use of time polynomials is considered. The programmed...     

Classification of the Uncertainty of Measurements

A discussion is given of questions arising when classifying uncertainties from the point of view of the structure of the measurement process.     

Effect of temperature and the initial state on the spalling fracture of alloy 36NKhTYu

The article presents the results of an experimental investigation of the effect of the temperature, the sulfur content, and the previous heat treatment on the strength and fracture of the alloy 36NKhTYu under loading by shock waves. The load levels corresponding to different stages of spalling fracture of specimens were determined in the temperature range from −196 to 750‡C. It was established that heating, increase of sulfur content, and hardening of the specimens lead to an imperceptible decrease of the dynamic strength of the alloy. The article presents the results of observations of the structure and nature of spalling fracture of the alloy by optical and electron microscopy. Translated from Problemy Prochnosti, No. 5, pp. 119–122, May, 1996.     

Effect of the initial state on spalling of copper

The results are presented of experimental examination of the effect of the grain size on the spoliation of copper. Levels of the loading pressure, corresponding to various stages of spollation, were determined for two initial states characterized by a mean grain size of 0.29 and 1.62 mm. The results show that for the material with the smaller grain these levels are approximately 0.2 GPa higher than for the material with the larger grain size.Translated from Problemy Prochnosti, No. 2, pp. 73–75, February, 1996.     

Damage of a steel plate from hypervelocity impact

We presents the results of damage of a carbon steel plate30 mm thick upon its loading by the impact of a steel ball5.55 mm in diameter at a velocity of up to7.4 km/sec. The dimensions of the crater formed and the bending flexure of the spalling layer are in good agreement with the results obtained upon a less intense loading of the target. One more feature of damage, namely, a crack passing through the target at the level of the crater bottom, has been revealed for the first time. Institute of Experimental Physics, Sarov 607200. Translated from Fizika Goreniya i Vzryva, Vol. 33, No. 1, pp. 119–121, January–February, 1997.