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Influence of electrode wire feed rate on base metal penetration and geometrical dimensions of deposited beads at submergedarc surfacing was studied. Four flux-cored wires of 1.2; 1.6; 1.8 and 2.0 mm diameter were used in the experiments. Feed rate regulation was performed in the range from minimum value Vf.max, at which a stable surfacing process can be in place for these conditions, and up to maximum value Vf.max = 450 m/h, which was determined by the characteristics of the used surfacing unit. It is found that at surfacing with high wire feed rates, there exists such an optimum ratio of feed rate and other surfacing parameters for each wire diameter, at which increase of this rate leads to reduction of penetration depth and share of base metal in the deposited metal at rising surfacing current. Results, obtained in this work, were successfully applied at wear-resistant arc surfacing of 3 mm steel sheets, and can also be used in selection of modes of arc surfacing of other parts, which to the greatest extent meet their operating conditions, and requirements to deposited metal and base metal penetration. [ABSTRACT FROM AUTHOR]

The design of specimens and methods for experimental evaluation of the fatigue life of multilayer deposited specimens under cyclic mechanical loading were developed. The design of specimens imitates the design of real deposited parts, which allows performing a comparative evaluation of the influence of chemical composition of the base metal and deposited layers, as well as methods and technology of surfacing separate beads or layers on their fatigue life. For studies of fatigue life of specimens, the corresponding loading schemes were chosen, which with certain assumptions reproduce cyclic power loads characteristic for real parts: large-scale gears, pressing screws of rolling mills, mill rolls, MCCB rollers, etc. The results of experimental studies of the cyclic life of specimens by the proposed methods are given. It was established that the developed investigation methods should be used for evaluation of the fatigue life of different parts when choosing materials, equipment and technology of restorative or manufacturing multilayer surfacing. [ABSTRACT FROM AUTHOR]