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This article presents the study of the effect of ultrafine titanium monocarbide (TiC) powder on the formation of the deposited metal structure. The effective particle size of the powder for the welding bath inoculation of low-carbon and low-alloy steels should be at least 600–700 nm (0.6–0.7 μm). The use of an inoculator powder with a more dispersed fraction was inappropriate from thermodynamic and economic points of view. With the increase in the content of ultrafine TiC powder in the coating of welding electrodes (0%–10%), the crystallites in the deposited metal decreased in size by 8–9 times, and they acquired a more equilibrium state (the shape factor increased by two times). The addition of various amounts of TiC powder to the melt of the welding bath did not result in a noticeable hardening of the deposited metal (Vickers hardness: 188–197 HV). [ABSTRACT FROM AUTHOR]

Features of centrifugal plasma surfacing using powders of three different alloying systems based on iron and nickel were studied. It is found that at centrifugal plasma surfacing the iron-based test powder has the best welding-technological properties. It allows producing deposited metal of 200Kh15D2MS2R type. The layer deposited with this powder, has a microstructure of uniform height and ensures increase of the sleeve wear resistance 5 – 6 times, compared to batch-produced ones, which are made from steel 70 and quenched by SHF. A design of the bushing component is proposed with replaceable surfaced sleeve, which is more adaptable to fabrication and allows repairing it by simple replacement of the worn sleeve. [ABSTRACT FROM AUTHOR]

Features of centrifugal plasma surfacing using powders of three different alloying systems based on iron and nickel were studied. It is found that at centrifugal plasma surfacing the iron-based test powder has the best welding-technological properties. It allows producing deposited metal of 200Kh15D2MS2R type. The layer deposited with this powder, has a microstructure of uniform height and ensures increase of the sleeve wear resistance 5-6 times, compared to batch-produced ones, which are made from steel 70 and "uenched by HFC. A design of the bushing component is proposed with replaceable surfaced sleeve, which is more adaptable to fabrication and allows repairing it by simple replacement of the worn sleeve. [ABSTRACT FROM AUTHOR]

In this article, for the first time, research of the defective frog wing of the 1/11 mark on the Latvian Railway has been carried out. In the process of which was collected, processed and the analysis of points defects on the Latvian Railway was carried out for eight compartments of the track distance during 2014, 2015 and 2016 (Developed a chief of defectoscopy shop V. Glotov, approved CD the chief of the distance V. Makedon). The frog wing of the 1/11 mark (the 60 E1 DO 04 07 frog type) was considered according to the basic classification of the defects, and an analysis and research of the cause of its fracture were carried out.

The influence of introducing tungsten and tungsten concentrate in powder-core wire on the structure, microhardness of the structural components, hardness, and wear of the applied metal layer is studied. For surfacing, tungsten-bearing powder wire (types H and E in the IIW classification) is produced in the laboratory. The fillers employed are KR-1 silicon powder (State Standard GOST 2169–69); MR-0 manganese powder (State Standard GOST 6008–82); PKhA-1M chromium powder (Technical Specifications TU 14-1-1474–75); VEL-1 vanadium (Technical Specifications TU 48-0533–71); PNK-1L5 nickel (State Standard GOST 9722–97); PAP-1 aluminum (State Standard GOST 5494–95); PVT tungsten (Technical Specifications TU 48-19-72–92); and PZhV-1 iron powder (State Standard GOST 0489–96). In some wire, tungsten powder is replaced by KSh-4 tungsten concentrate (State Standard GOST 213–83), produced by OAO GK AIR. The carbon-bearing reducing agent employed is gas-purification dust from aluminum production. Its composition is as follows: 21.00–43.27 wt % Al2O3, 18–27 wt % F, 8–13 wt % Na2O, 0.4–6.0 wt % K2O, 0.7–2.1 wt % CaO, 0.50–2.48 wt % SiO2, 2.1–2.3 wt % Fe2O3; 12.5–28.2 wt % Ctot; 0.03–0.90 wt % MnO, 0.04–0.90 wt % MgO, 0.09–0.46 wt % S, and 0.10–0.18 wt % P. The wire (diameter 5 mm) is produced on laboratory equipment. An ASAW 1250 system is used for surfacing, in the following conditions: Is = 400–450 A; Uarc = 32–36 V; Vs = 24–30 m/h. In surfacing, five metal layers are applied, under a layer of AN-26S flux and flux based on slag from silicomanganese production. The chemical composition of the applied metal is determined, and metallographic data are obtained: the size of the former austenite grain, the size of the martensite needles, and the content of nonmetallic inclusions are determined. Wear tests are conducted, and the hardness and microhardness are measured. The use of tungsten concentrate instead of tungsten powder in surfacing is shown to be possible in principle. The degree of tungsten extraction is calculated. For type-H wire, the replacement of tungsten powder by tungsten concentrate does not increase the content of nonmetallic inclusions in the metal layers applied; the primary austenite grain size is decreased. For type-E wire, the use of tungsten concentrate tends to decrease the primary austenite grain size and the size of the martensite needles and also increases the microhardness of martensite within the applied layer. The replacement of tungsten powder by tungsten concentrate in class-H wire considerably increases the hardness and wear resistance of the applied layer. [ABSTRACT FROM AUTHOR]

In this article, for the first time, research of the defective frog wing of the 1/11 mark on the Latvian Railway has been carried out. In the process of which was collected, processed and the analysis of points defects on the Latvian Railway was carried out for eight compartments of the track distance during 2014, 2015 and 2016 (Developed a chief of defectoscopy shop V. Glotov, approved CD the chief of the distance V. Makedon). The frog wing of the 1/11 mark (the 60 E1 DO 04 07 frog type) was considered according to the basic classification of the defects, and an analysis and research of the cause of its fracture were carried out. [ABSTRACT FROM AUTHOR]