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In the present research, Al-Al2O3 composites with 5 vol.-% alumina were produced by stir casting at a temperature of 800°C. Two different particle sizes of alumina were used as 53-63 and 90-105 μm. The microstructure of the samples was evaluated by SEM. In addition, the mechanical properties of the samples were measured, and hence, the optimum temperature and particle size of alumina to be added to the Al matrix were determined. The results demonstrated the positive effect of alumina on improving the properties of Al-Al2O3 composites.

The implementation of the method made possible to obtain the films of cathode material up t0 20 μm thickness with good adhesion properties. The thin film phase analysis differs from initial material one: the interference lines corresponded to pyrite and low temperature piritinite of α and γ iron modifications are identified. The phase crystalline structure constituent has been determined using Sheerer equation and equals 10-20 nm.

The method was realized for the qualimetry estimation of complex influence of dimensionless combinations of meaningful factors upon the degree of deformation by the alternating twisting, which determining the proper properties of steel wire at multiple drawing. Limitations of this method were defined: impossibility of its using for the analysis of alternating values of response function.

The results from bainitic rail steels were compared with those for 870 MPa grade pearlitic rails steel. It was found that in the as rolled slow cooled condition rail properties such as fracture toughness, Charpy impact energy, and endurance limit were superior to those of 870 MPa grade pearlitic rail steel.

Hydrogen embrittlement of a copper precipitation strengthened and niobium microalloyed shipbuilding steel on cathodic charging in synthetic sea water has been studied using a slow strain rate technique. The effects of strain rate and potential applied for hydrogen charging have been studied. The results are discussed in the light of the existing models of hydrogen–dislocation interaction and hydrogen induced microvoid coalescence.

Carbide reinforced steel composites are useful in extensive wear resistance applications. Tensile strength measurements showed that the ultimate tensile strengths varied between 800 and 850 MPa for composites containing 0, 3–0, 7 wt.% Ti. Some composites show better wear resistance properties in comparison with low alloy steels.

The present paper reports an investigation into the microstructural changes occurring in a ferritic–austenitic duplex stainless steel during solution nitriding. Both microstructure and microtexture modifications as a result of nitrogenation have been studied, in addition to the interaction between solution nitriding, grain growth, and texture. Hence, the texture of the austenite in this region was different from that in the duplex region.

Generalized problem of optimization of acid etching technology is formulated and mathematical formulation in the form of conditional task of mathematical programming is given. Empirical dependence equations of corrosion rate and scale removal time on etchant temperature and strength are given.

Research work is directed on working out of structurally of astringents compositions hydraulic, air and autoclaved hardening, including a waste of a metallurgical complex. As a result of work possibility of use of the specified waste in compositions of cement, concrete, gypsum and a silicate brick is established, and also their optimum dosages are defined.