The paper is devoted to studying the possibility of creating an amorphous state in the metallic materials in the electrospark action process. Produced by powder metallurgy FeWMoCrBC crystalline alloys of two different compositions that were used as anodes for the coating onto the steel 1035 substrate by electrospark deposition technology. Study of mass transfer kinetics during the deposition of both compositions showed relatively high values of gain cathodes. Thus, the maximum mass transfer efficiency achieved using an electrode with a high iron content due to better adhesion to the steel substrate. It is found that by coating had a thickness of about 40 microns and had the metallic glasses structure from XRD data. Based on the results of differential scanning calorimetry revealed that recrystallization of the coating material occurred at annealing temperature exceeding 814 -825°C. XRD data of the samples after annealing at 1200°C showed that the amorphous structure is crystallized into carbides iron, tungsten and boron; borides iron, molybdenum and tungsten; as well as is observed metallic chromium and tungsten. The surface roughness of coatings was 7 microns. Were conducted tests on the durability of FeWMoCrBC metallic glass coatings to microabrasive wear, and dry sliding abrasion with a silicon carbide abrasive disk. It is shown that the FeWMoCrBC amorphous electrospark coatings improve wear resistance and microhardness of the steel 1035 in 2 -4 times, respectively. In general, despite the significant differences in the composition of the electrode materials obtained from the coating of metallic glasses had very similar properties. Работа посвящена изучению возможности создания аморфного состояния в металлических материалах в процессе электроискрового воздействия. Методом порошковой металлургии получены FeWMoCrBC сплавы двух различных составов, которые использованы в качестве анодных материалов для нанесения покрытий на подожки из стали 35 методом электроискрового легирования. Изучена кинетика изменения масс электродов в процессе осаждения по-крытий. Установлено, что при использовании электрода из FeWMoCrBC сплава с более высоким содержанием же-леза привес катода выше за счет лучший адгезии к стальной подложке. Толщина созданных покрытий составляет около 40 мкм. По данным рентгеновской дифрактометрии покрытия обладают структурой, аналогичной металличе-ским стеклам. На основе результатов дифференциальной сканирующей калориметрии определено, что материал по-крытий начинает кристаллизоваться в процессе нагрева при температурах свыше 781 -786°С. После отжига при тем-пературе 1200°С в электроискровых покрытиях наблюдаются карбиды железа, вольфрама и бора; бориды железа, молибдена и вольфрама; а также хром и вольфрам как отдельные фазы. Шероховатость покрытий по критерию Ra была около 7 мкм. Испытания стойкости покрытий из металлических FeWMoCrBC стекол к микроабразивному из-носу, а также сухому трению об абразивный диск из карбида кремния, показали, что износостойкость аморфных электроискровых покрытий выше износо...

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Coatings based on amorphous metals with a different number of elements: nickel, cobalt, molybdenum and tungsten, were obtained on steel 35 by electrospark deposition in a mixture of crystalline granules.The thickness of the deposited coatings was 20 to 33 μm. X-ray diffraction analysis showed a wide halo in the range of angles 20-43° that indicates on a predominance of the amorphous phase in the coating composition. The content of the amorphous phase, depending on the coatings composition, varied from 81 to 99 vol.%. The smallest fraction of the amorphous phase was observed in the coating without molybdenum. According to the EDS analysis, it was shown that the concentration of elements along the cross-section of coatings was constant that indicates on a homogeneity of the composition of the deposited coatings. A study by the scanning electron microscopy in phase contrast mode showed that the coatings had a homogeneous structure and did not have a precise boundary with the substrate demonstrating a good adhesion of the coatings to the substrate. Potentiodynamic polarization tests in 3.5 % NaCl solution have shown that amorphous coatings can improve the corrosion resistance of the steel 35 surface by up to 5 times. Tungsten reduced the rate of electrochemical corrosion of coatings, while cobalt lowered the corrosion properties of the coatings. A high-temperature corrosion test for 100 hours at temperature of 700°C showed that the samples with coatings were oxidized 3.4 to 7.9 times less than steel 35. Barrier properties of coatings without tungsten under high-temperature gas corrosion were 2.3 times lower than those of coatings without cobalt. This means that tungsten improves the corrosion resistance of amorphous alloys, whereas cobalt reduces it.

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