Study of properties of manual metal arc electrodes for gray cast iron defects repair works

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. 20°C. 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 cladding. Practical 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.