Evaluation of strain and material flow in sheet-metal forming

The present paper is concerned with the method of deformation networks in the range of stampings drawing from sheet-metal. The influence of circular grids, made by embossing with the use of special apparatus for grid marking, upon sheet-metal is described. The sizes of impressions and the influence of the embossed circular grids upon the sheet-metal properties were determined for two cases of adjustment of apparatus for making impressions—on impression depth of 0.06 and 0.05 mm. In both cases of apparatus adjustment from measured values of HV 0.01 in the direction normal to the sheet-metal surface in the place under the impression and in the surroundings, it was found that in the embossing of the impression on the sheet-metal a substantial influence upon the ferrite grain microhardness does not occur deeper under the sheet-metal surface.