Mechanical Characteristics and Wear Resistance of the Cladding Layers Obtained by Melting of Cored Wires with Simultaneous Vibration of Substrate

A wear proof layer was obtained by applying vibration with a frequency of 100 Hz and amplitude of 0; 70; 300 μm to the cored wire of Fe-Cr-B-C doping system during welding. It was shown that horizontal vibration affects the grinding process of boride inclusions: their average diameter reduces from 175 to 5 μm, and the amount of (FeCr)2B plastic phases increases during the redistribution of phases. Wear resistance of the metal, which was deposited using horizontal vibration with an amplitude of 300 μm, increases by 2.3-2.5 times due to wear with the fixed and unfixed abrasive material, and by 2.8 times due to wear under impact loads. For restoration and strengthening of large-size parts, it is proposed to add Al-Mg powder (Al = 47 - 53 %, Mg = 53-47% wt. %) to the CW charge to increase wear resistance of the deposited metal of the Fe-Cr-B-C system. This contributes to the dispersion of the boride inclusions, the average diameter of which decreases from 70 to 5 μm. In the structure of the deposited metal of the Fe-Cr-B-C system, inclusions of the complex alloyed nitrides are extricated with an average size less than 1.0 μm. As a result, the average value of microhardness increases from 700 to 900 HV. Wear resistance of the deposited metal increases by 1.5 times due to wear with the fixed and unfixed abrasive material, and by 2.0 times due to wear under impact loads

Optimization of the arc spraying process parameters of the Fe–base Mn-Si-Cr-Mo-Ni coatings for the best wear performance

In this paper, the use of Fe – base Mn - Si - Cr - Mo - Ni and Fe – base Mn - Si - Cr wires for thermal arc spraying is presented. For this purpose the mechanical and physical properties of coatings were evaluated. The quality of the coating’s was dependent on the selected equipment, spray materials, technological parameters of the spray and spray technology. The aim was to qualify and optimize the parameters for spray coating to get the best coatings properties with good tribological properties. A ll coatings were deposited on mild steel S235JR substrates. Two experimental cored wires of unique chemical composition – STEIN - MESYFIL 932 V and STEIN - MESYFIL 954 V – were used for thermal arc spraying. The wires of 1.6 mm diameter were used for the surfa cing material. Hardness, porosity and oxide measurements were used to verify the spray parameters and analyze the coatings. Rubber wheel test, which is based on the standard ASTM G65, was used. Dry - sand, rubber - wheel procedure according ASTM G65 was used to investigate low stress abrasion, whereas for high stres s abrasion investigations a rubber wheel was used. This experiment was carried out by changing the speed of disc friction, travel distance and measuring the mass loss of surface friction. Miller Test according to ASTM G75 - 95 Standard was carried out in experiment with friction. The samples were immersed in water with corundum and polished with 22 N load, for 8 hours. Furthermore a correlation was performed between the spraying current and voltage parameter. The coatings’ cross sections were examined using s canning electron microscope (SEM) and optical microscopy. The influence of the composite components of the coatings’ microstructure, such as porosity, microhardness, oxide inclusions, on the tribological properties of thermal sprayed coatings is discussed in this paper