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In this article, the development of a technology for the production of clinkers and cements based on them using previously unexplored alternative sources of local raw materials in Karakalpakstan is studied, is an effective solution to the problem of covering the cement industry’s construction industry needs. Development of practical recommendations on the technology for obtaining Portland cement clinkers and cements based on the raw materials of Karakalpakstan. The study of the chemical and mineralogical composition of the raw materials of Karakalpakstan with the aim of their application to obtain high-quality clinkers and cements based on them. For raw mixes, which include limestone from the Dzhamansay-2 deposit, the clay component of the Berkuttau site, an iron-containing cinder from Almalyk mining-and-metallurgical integrated works, and gypsum stone from the Northern Dzhamansay deposit, the optimal firing temperature is 1450 ° C, which corresponds to the classical temperature index Portland cement clinker production. Raw mixtures based on the tested raw materials are highly reactive. When firing two-component feed mixtures using limestone of the Dzhamansay-2 deposit and basalt rock of the Berkuttau section, the optimum clinker sintering interval is 1400-1420 ° C;. Physical and mechanical tests have established that, on the basis of the tested raw materials (limestone of the Dzhamansay-2 deposit, the clay component of the Northern Dzhamansay deposit, the basaltic rock of the Berkuttau site and iron-containing additives), clinkers can be produced for general construction and sulfate-resistant cement grades of at least “400”, according to technological indicators fully meeting the requirements of State standard 10178; State standard 30515 and State standard 222 66.

Complex approach to studying both qualitative and quantitative friction and wear characteristics of laser-clad layers has been applied. Both type and value of wear, friction factors have been determined as depended of the coating composition, load and temperature in dry friction. Comparative analysis between laser cladding and plasma spraying has been carried out.

There is a well-based correlation between the pulsating amplitude σ A(R = 0) and the alternating amplitude σ A(R = – 1) in fatigue testing of sintered iron and steel which permits to predict the mean stress sensitivity and the pulsating amplitude if the alternating endurance limit σ A(R = – 1) has been measured. Without loss of precision the relationship can be extended from smooth unnotched specimen geometries to notched geometries if only the stress concentration factor is known. The coefficients of the predictive equation depend on the brittleness of the material, a systematic approach to take the brittleness into account is still missing. In Haigh diagrams, the slope of the σ A–σ m diagram with tensile mean stresses can be linearly extrapolated also into the compressive mean stress range σ m < 0.

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