Papers by Keyword: Arc Spraying

Abstract: This article deals with studying the technology of electric arc spraying of the eccentric body by selection of the copper-steel pseudo-alloy for spraying a covering. The part durability with the placed covering depends on the technology of spraying and the properties of the sprayed material. By increasing the strength of adhesion of the covering to the base it is possible to establish the optimal indicators of the coating mode. It became the main criterion of studying the arc spraying technology from the mathematical point of view.

Abstract: Multiple use of pan concentrate from placer deposits directly in technical process without prealltoment of pure components could become one of promising directions in the field of receiving wide range of multicomponent metal and ceramic powdered materials. In this paper as the object of comparative examination, we present the hemimethylated plating made of exploited experimentative flux cored wires based on industrial Ni-Cr-B-Si system powder modified with rare-earth elements of concentrated complex from Tomtor mineral assets Republic of Sakha (Yakutia). The structure of received plating is heterogeneous and has oxidation coating as boundaries. According to the data of the phase shift analysis plating predominantly consist of Fe-Ni austenitic alloy phases with the Cr, Si carbide and Cr boride precipitation strengthening, plating generally consist of Al2O3, Cr2O3 и Fe2O3 oxide. The research of the plating ultimate composition testifies the equable allocation of main and alloying elements, local location of some elements in the structure of the plating. Microhardness of flux cored wire plating substantially depends on composition and fabricated structure. It has been established that the introduction of rare earth elements provided the formation of strengthening phase with the high hardness of plating resulting in wear resistance increase.

Abstract: In this paper, a kind of FeCrBSiMnMoW amorphous nanocrystalline composite coating was prepared on the steel matrix by arc spraying, and the microstructure and properties of the coating were studied. The results show that the coating owns compact structure and low porosity. The coating is composed of amorphous phase and α (Fe, Cr) nanocrystalline phase, and the nanocrystalline phase is uniformly distributed in the amorphous matrix. The initial crystallization temperature is above 587.5 °C, which indicates the coating has good thermal stability. The Vickers hardness of the coating is around HV_0.3= 1150. The wear mechanism of the coating is abrasive wear with a friction coefficient of 0.434 and the wear loss rate of only 3.3×10^-5 mm³/Nm, which shows excellent wear resistance of this kind of coating.

Abstract: Processing by thermal spray metallization is a process widely used in industrial area. Surface Coatings systems using electric arc spray metallization opens up a range of new possibilities for refurbishing and bringing the parameters according to the technical documentation, the main objective is to ensure a high resistance to wear and corrosion. Through this research I set a schedule to settle the experimental influences how technological parameters on interface material - deposited layers.

Abstract: Arc spraying (AS) is a thermal spraying method. The spraying distance represents one of the main technological parameters. EDAX analysis, performed on the sprayed layers (SDA and SDS), have shown differences between the initial chemical composition of the filler material and of the obtained layers. The quantitative variations determined for Ni, Fe and Cr can be explained by: the volatilization process of the chemical elements from the electric arc area; losses increase with increasing the length of the spraying jet.

Abstract: In this paper the new process of arc spraying was researched on CuCo2Be alloy surface,the high strength and high wear resistance Cr3C2/Fe coating were prepared on CuCo2Be alloy surface by adopting a series of different arc spraying process parameters. Based on the test the arc spraying process parameters was optimized, the optimized result was: spraying voltage was 38V, the current is 180A, spraying distance was 150mm, spraying air pressure was 0.7MPa, the bonding strength of the coating and the substrate was 30.5MPa; and the thermal shock resistance of coating Cr3C2/Fe was studied in detail by different spraying process parameters, it was showed: thermal shock resistance of the coating was best by spray low voltage and low current process. By using microhardness tester, super depth of field microscope, SEM, EDS and XRD, mechanical properties, microstructure, phase composition and its content distribution of Cr3C2 / Fe coating were studied, the study results were showed: the micro-hardness of coating was 992.75HV, coating was a typical lamellar structure, and a small amount of pore and oxides in the coating; the mainly phase of coating included: Fe, Fe-Cr, C0.14 Fe1.86 and Fe7C3.

Abstract: The paper aims to determine, through experiments, the necessary force for detaching the deposited layer (SD) from the support layer (SB). The thermal sprayed coating was formed by successive deposition of two sub-layers, one for anchorage and the second for corrosion resistance. Shear adhesion strength tests were performed on a specialized stand, while force (F_ad) and displacement (x) values were recorded with a data acquisition system. The variation curves, F_ad = f (x), outline the evolution of the detachment process of the sprayed layer and the two main components of the deformation process: slip and breakage.

Abstract: This paper has introduced moulding method of electroforming combining with arc spraying. Compared with electroforming moulding, it has shortened moulding production cycle and reduced cost of production. Compared with arc spraying moulding, it has improved mould’s surface quality and hardness.

Abstract: A Fe-based amorphous composite coating was deposited on a carbon steel substrate by arc spraying, and remelted with different laser energies by the Nd: YAG laser cladding system, in order to improve the mechanical properties of the coatings. The microstructure and microhardness of the composite coatings were investigated. The variation of harndness was measured as a function of the modified layer depth, which indicates that the laser remelting improves the bonding strength and hardness. Increasing the laser power, the quality of coating gets better, but the amorphous volume fraction decreases. It is obtained that the optimal laser electric current for the coating of 280 μm thickness is about 300 A, in which the remelted coating with medium energy densities has the highest average Vickers hardness of 741. Through the volume fraction change of the nanocrytals, the hardness of the composite coating is regulated by the laser power input, which amplified the application fields of the amorphous coatings.

Abstract: In order to improve the organization, reduce the porosity, compact the structure and enhance the corrosion resistance of the coating, Zn-Al-Mg-RE coating system was prepared by high velocity arc spraying. The surface appears, phase composition and electrochemical properties of the coating were characterized by scanning electron microscope, X-ray radiation diffaction and electrochemical workstation. The results indicated that the coatings were compact. The coatings were mainly zinc and aluminum phase. In corrosion of immersion, the reaction resistance and coating resistance of coatings quickly become bigger, the surface of coatings become more compact, and the corrosion reaction is more difficult. Electrochemical tests showed that the coating had excellent corrosion resistance. The electrochemical protection and self-sealing effect of coatings can have long-term effects on anticorrosion.