Підвищення експлуатаційних властивостей поверхонь деталей при нанесенні наноструктурованих нітридних покриттів

Abstract

В роботі було досліджено вплив наноструктурованих нітридних пориттів на основі Ti, Ti-Zr, Ti-Al, Ti-Cr, отриманих методом магнетронного розпилення на поверхню деталі, на покращення фізико-хімічних характеристик виробу та здійснення систематичного огляду особливостей нітридних покриттів на основі Ti, Ti-Zr, Ti-Al, Ti-Cr. Розглянуто фазовий склад покриттів, який залежний від вимог отримання (структури елементів покриття, перебування заготовок деталей у вакуумній камері відносно місця, де проводиться напилення). Розпізнано структуру та визначено основні властивості наноструктурованих нітридних покриттів. Охарактеризовано передумoви і можливості застосування наноструктурованих нітридних покриттів різного складу, отриманих методом реактивного магнетронного осадження.

The attitude in current materials science to the change of the surface of active components is considered relevant, the purpose of which is to provide details of the innovative system of operational and physico-mechanical characteristics. This method of formation of coatings from material nitrides is used in various areas of strengthening the surfaces of parts, as they extend their service life, reliability and durability. Reactive magnetron sputtering provides good mechanical properties such as low thermal conductivity, corrosion resistance, wear resistance and high hardness. The purpose of the work is to improve the operational properties of the surfaces of parts when applying nanostructured nitride coatings based on Ti, Ti-Zr, Ti-Al, Ti-Cr, which is due to the need to obtain coatings with a diverse structure and optimal properties for the operation of products in certain conditions; study of the influence of the structural characteristics of the components of nitride coatings on the physical and mechanical characteristics of the coatings. To achieve the given goal, the following tasks were identified and set in the study: 1. Conduct an analytical review of literature sources regarding varieties, production and characteristics of nanostructured nitride coatings. 2. To implement an experiment on obtaining nanostructured nitride coatings of various compositions by the method of reactive magnetron deposition. 3. Consider the phase composition of coatings applied by the method of magnetron deposition, which depends on the requirements for obtaining (the structure of the coating elements, the location of the workpieces in the vacuum chamber relative to the place where sputtering is carried out). 4. Recognize and characterize the structure and determine the main properties of nanostructured nitride coatings. 5. To characterize the prerequisites and possibilities of using nanostructured nitride coatings of various compositions obtained by the method of reactive magnetron deposition. The object of research is nanostructured nitride coatings based on Ti, Ti-Zr, Ti-Al, Ti-Cr, produced by magnetron deposition. The subject of the study is the phase composition, structure and properties of nitride coatings based on Ti, Ti-Zr, Ti-Al, Ti-Cr obtained by magnetron deposition. Research methods. Methods of experimental and theoretical level; methods of obtaining coatings with the help of physical deposition in a vacuum - magnetron sputtering; mechanical processing; research of the surface of nitride coatings. obtained using magnetron deposition methods - electron and atomic force microscopy, X-ray structural analysis. Nanostructured nitride coatings were formed by magnetron deposition. The study of nitride coatings by magnetron sputtering on the surface of the part was carried out to improve the physical and chemical characteristics of the parts on which these coatings were applied. A systematic review and analysis of the features of nitride coatings obtained by the method of magnetron sputtering was carried out. A high-quality protective coating has proven itself on the basis of chromium nitride, therefore it has good chemical and mechanical properties, therefore it is now widely used in production. Scientific novelty. Study of the effect of nanostructured nitride coatings based on Ti, Ti-Zr, Ti-Al, Ti-Cr, obtained by magnetron sputtering on the surface of the part, on the improvement of the physical and chemical characteristics of the product and the implementation of a systematic review of the features of nitride coatings based on Ti, Ti-Zr , Ti-Al, Ti-Cr obtained by magnetron sputtering. The scientific novelty of the obtained results: 1. The TiN coatings studied in the work are dense, have low surface porosity and a small content of the α-Ti droplet phase, in all sputtering modes a coating with a columnar structure of TiN grains is formed. A tendency to decrease the size of the grains was established with a decrease in the arc current and the pressure of the reaction gas in the chamber. 2. Phase analysis of the obtained coatings (TiCr)N shows that they consist of a solid solution of Cr in titanium nitride. The coatings also contain α-Ti and Cr. (Ti, Cr)N is a coating that has higher resistance to oxidation and retains its properties at higher temperatures compared to TiN and CrN coatings. The (Ti, Cr)N coating is characterized by a significant stabilization of microhardness over time. The effectiveness of strengthening with this coating depends on the size of the tool being strengthened. A multi-component composite nitride coating containing (85% Ti and 15% Cr) provides maximum wear resistance of the small-sized cutting tool. 3. Experimental data of Ti-Al-N and Ti-Zr-N coatings show that on a globular surface, with an increase in the thickness of the coating, the formation of a branched system of input angles along the boundaries of the hemispheres occurs, which contributes to an increase in the rate of coating formation under the selected conditions and is manifested in coarsened structure of globules, covered with single (Ti-Zr-N) and numerous (Ti-Al-N) pseudo-facets (100). 4. The patterns of friction and wear of TiN-based coatings applied to P6M5 high-speed steel were investigated under conditions of frictional contact with steel 45. An increase in the coefficient of friction with increasing load was observed during tests of P6M5 steel without coating and a slight decrease during tests of coating with lubricant . What is common both for friction on coated surfaces and on uncoated P6M5 steel is that the minimum values of the friction coefficient are observed when lubricated with grease, and the maximum values are observed during dry friction. 5. It was found that the coatings have a hardness in the single-layer version - TiN - 23 - 25 GPa, (Ti, Cr)N - 28 - 30 GPa, and in multilayer TiN-CrN coatings, the hardness is 25 - 40 GPa. Experiments show that the microhardness of multilayer nanocoatings containing compounds from layers with a microhardness ≥ 20 GPa increases by approximately 2 times, i.e. reaches values ≥ 40 GPa. 6. The nano-layer structure with limited nitride grains in the nano-range was favorable for increasing the mechanical characteristics for the multilayer coating.