[Show abstract][Hide abstract] ABSTRACT: Purpose: Purpose of this paper: Study of robotized GMA metal-cored wire surfacing of one-, two- and threelayers stringer bead and weave bead deposits has been carried out.Design/methodology/approach: The dilution of deposits, structure, hardness, WC carbide morphology andabrasive wear resistance type metal-ceramic as per ASTM G65, was determined.Findings: It was shown that the abrasive wear resistance of stringer bead deposits is higher than weave beaddeposits. Study of robotized GMA surfacing process with EnDOtec DO*11 wire of diameter 1.6 [mm], applyingweaving (oscillation) technique of surfacing, showed that it is possible to produce high quality of deposits ina wide range of surfacing parameters (heat input). Contrary to stringer bead deposits, weave bead deposits aretransverse cracks free which can be caused by thermal stresses in the deposits.Research limitations/implications: The mechanism of deposit formation (shaping), especially the control ofdilution, shape of fusion zone and penetration depth, depending on parameters of surfacing and the trajectoryand parameters of oscillation of the surfacing torch demands further investigations and detailed studies.Practical implications: The technology can be applied for wear plates manufacturing.Originality/value: Improve of the wear resistance of wear plates.
[Show abstract][Hide abstract] ABSTRACT: Purpose: Purpose of these researches was to determine influence of GMA metal cored wire surfacing parameterson the abrasive and erosive wear resistance of the one layer and three layer weave bead cermetal deposits.Design/methodology/approach: One layer and three layer weave bead deposits were GMA surfaced usingmetal cored wire (nickel based + 54%WC) 1.6 [mm] dia. To determine quality of deposits Visual Inspection,MT examinations, hardness HRC and HV10 measurements on the ground surface of deposits, macrostructureand microstructure observations, abrasive and erosion wear resistance tests were done.Findings: Hardness of deposits tested is in the range from 453–517 HV10 (44.5-47.9 HRC) and is a function ofthe value of heat input of surfacing. WC carbides population density, size and distribution in nickel alloy matrixof deposits tested is a function of GMA heat input of surfacing. Low heat input of surfacing insures uniformdistribution of WC carbides on the cross section of deposits. The low heat input GMA surfaced weave beaddeposits provide 10 times higher abrasion wear resistance and 4.2 times higher erosion wear resistance thanHARDOX 400 steel plate.Research limitations/implications: Results of this paper is to increase quality of GMA cermetal deposits.Originality/value: Hardness of deposits can not be treated as the abrasion and erosion wear resistance indicator.
[Show abstract][Hide abstract] ABSTRACT: Purpose: of these researches was to determine influence of MMA technique and surfacing parameters of gray cast iron using CASTOLIN 27 coated electrodes on quality of deposits.Design/methodology/approach: single layer weave bead deposits and one layer overlapped multi weave bead deposits were MMA surfaced on gray cast iron type GG25. All deposits were surfaced on no preheated gray cast iron plate. To determine quality of deposits hardness HRC measurements on the cross section of deposits, macrostructure and microstructure observations were done.Findings: properties of deposits strongly depend on MMA surfacing parameters and the technique of surfacing. Increase of surfacing current (dilution) provided increase of deposits hardness. One layer overlapped multi weave bead deposits MMA surfaced with no control of interpass temperature showed higher HRC hardness then deposits MMA surfaced with interpass temp. 20oC.Research limitations/implications: for complete information about properties of manual metal arc electrodes for gray cast iron cladding it is needed to compare properties of CASTOLIN 27 with other coated electrodes for gray cast iron claddingPractical implications: results of this paper is to increase quality of deposits on gray cast iron.Originality/value: properties of deposits strongly depend on the technique of MMA surfacing.