Composition of C–Si–Mn–Cr–W–V powder wire and quality of surfacing

The influence of the composition of powder wire on the properties of the applied layer on steel samples is studied in the laboratory. If amorphous graphite in 35V9Kh3SF powder wire is replaced by material containing carbon and fluorine, the porosity of the applied layer is reduced, and fewer nonmetallic inclusions (including row oxide inclusions and undeformable silicates) are present. Statistical analysis of the experimental data illustrates the influence of the carbon equivalent of the 35V9Kh3SF powder wire on the hardness of the applied layer (including the mean surface hardness and the microhardness of martensite). With increase in the carbon equivalent calculated by the Paton Institute’s formula, the hardness of the applied layer linearly increases.     

Titanium Carbonitride Composite with Iron ― Chromium Binder

Wetting of titanium carbonitride with iron ― chromium alloys has been studied in the concentration range 2-30 mass% Cr. Chromium is shown to be a surface-active additive that decreases wetting angles in the TiCN ― (Fe ― Cr) system. The results of the investigations made it possible to choose the optimum composition of titanium-carbonitride material. A technology has been developed for the fabrication of new composite and some properties of this composite have been determined.

     

Recovery of nickel from hydrate pulps at amino carboxylic cationites

Regularities of the sorption of nickel from hydrate pulps using amino carboxylic cationites ANKB-35, S 930, and TP 207 are investigated. Kinetic curves and sorption isotherms for these cationites are constructed. It is revealed that it is reasonable to absorb nickel from pulps at pH = 4–5. The desorption of nickel from cationites is investigated. It is shown that cationite TP 207 possesses the maximal sorption capacity.     

Wear Resistance of Plasma-Sprayed Coatings in Intensive Abrasive Wear Conditions

The abrasive wear resistance of plasma-sprayed oxide ceramic (Al2O3 and Cr2O3) and clad cermet ((Ti–Cr–C)–30% Ni and (TiC)–30% Ni) coatings was studied. The wear characteristics of the coatings such as wear rates, friction forces, friction coefficients, and wear groove depth determined with two methods were compared. The wear test methods included simulation of the friction process using loose abrasive particles and reciprocal ball-on-disk friction using a diamond indenter. The plasma-sprayed TiC-based coatings showed the lowest wear rate and can be applied to protect equipment parts subjected to intensive abrasive wear. The wear loss of the (Ti–Cr–C)–30% Ni and (TiC)–30% Ni coatings determined by friction against loose abrasive particles was 10–17 μm, while the wear loss of the oxide ceramic coatings was 20–42 μm, being 2–2.5 times higher on average.     

Electric-spark alloying of structural alloys with a composite based on TiCN-AIN

The mass-transfer kinetics, the mechanism of formation, the tribotechnical characteristics, and the resistance to high-temperature oxidation of a coating formed on the hard alloy WC — 6% Co and on the titanium alloy VT6 by electric-spark alloying with electrode material based on TiCN — AIN with an Fe — Cr binder have been investigated. The phase distribution of the components in the coating was shown to be the same for both alloys. Electric-spark alloying of WC — Co and VT6 was found to reduce their wear by 33 and 60%, respectively. Moreover, the working temperature of the coated WC — Co alloy increased by 160 deg compared to the original surface. Translated from Poroshkovaya Metallurgiya, Nos. 5–6(413), pp. 21–29, May–June, 2000.     

Spillway construction at the Irganai HPP in Dagestan

Experience with the opening of inclined workings is presented. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 6, June 2008, pp. 2–6.     

Thermal analysis of coal and water-coal suspensions

Thermal analysis of coal and water-coal suspensions is discussed. It is found that coal of different ranks is characterized by different initial and final combustion temperatures.     

Structure and wear regularities of coatings from composite metal-ceramic materials of the SiC-Al<Subscript>2</Subscript>O<Subscript>3</Subscript>-Ni-Al system

The structure of coatings from composite material containing the SiC-Al₂O₃ wear-resistant component and a Ni-Al metallic binder has been investigated. The coatings have been produced by the high-velocity air fuel deposition (HVAF) onto medium-carbon steel. The tribotechnical characteristics of these coatings have been studied in dry friction in air and special features and regularities of their wear mechanisms have been defined.