Electrical erosion of W(Mo)-Cu composition in electrospark machining a hard alloy in a carbon-bearing liquid. II. Concentration dependence of wear and removal rate

Conclusions The concentration dependences of relative wear and productivity of the tungsten-copper and molybdenum-pseudoalloys in electrospark machining VK20 hard alloy were constructed. These dependences are characterized by the extreme values and are explained by the mechanism of their erosion (described in report 1) in the carbon-bearing liquid with an allowance made for the formation of a mixture of refractory metal and its carbide on the working surface.Translated from Poroshkovaya Metallurgiya, No. 2(302), pp. 78–81, February, 1988.     

Electrospark alloying followed by laser treatment of high-speed steel cutting tools

The effect of electrospark and laser alloying with WC-, TiC-, and TiN-based electrodes on the physicomechanical and working properties of the high-speed steels R6M5 and R6M5K5 was investigated. Laser treatment of electrospark coatings based on refractory compounds increased hardness and heat resistance, and improved the contact properties of cutting tools in their interaction with the chip, thus increasing wear resistance. The optimal conditions of electrospark and laser alloying were determined.Materials Science Institute, Ukrainian Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 5–6, pp. 11–15, May–June, 1996. Original article submitted October 18, 1994.     

Mechanical properties of sintered materials

Published as a discussion in continuation with the series of papers [1, 2] on mechanical properties.     

Dynamics of uniaxial tension of a viscoelastic strain-hardening body in a system with one degree of freedom. Part 3. Hydraulic loading of the system

We analyze the motion of an open mechanical system with one degree of freedom used as a model of uniaxial tension of a viscoelastic strain-hardening body in a machine with hydraulic drive creating a variable force and, at the same time, playing the role of a damping element. It is shown that a nonautonomous fourth-order dynamical system with stable periodic or aperiodic solutions (depending on its control parameters) may serve as a model of the transient processes of motion in the analyzed system. Due to a significant decrease in the viscous resistance of the system caused by the presence of the hydraulic drive, the aperiodic attenuation is typical of the transient process. It is shown that systems with hydraulic elements differ fundamentally from mechanical systems without elements of this sort. Frantsevich Institute of Problems in Materials Science, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Problemy Prochnosti, No. 1, pp. 42–61, January–February, 2000.