Experimental investigation on the temperature distribution in the shearing zone during sheet metal blanking

Blanking is a manufacturing technology where large quantities of blanked parts must be manufactured without interruptions, like reworking the tool, to achieve an economically production. Therefore a capable process is indispensable to avoid inadequate part quality or premature failure of the tool because of wear. The blanking process is affected by the press, tool parameters and the material properties of the blanked sheet metal. However, another important factor is the occurring temperature in the shearing zone of the sheet metal due to the dissipation of nearly 95% of the plastic work during blanking and as well as frictional heating. This temperature rise impacts the blanking process features such as tool-wear, material properties of the sheet metal and resulting cut edge quality. At present, no reliable data of the occurring temperature in the shearing zone is available. Against this background, a thermoelectric method to measure the resulting temperature distribution during the blanking process on the cutting edge of the blanking punch is introduced in this paper. Experimental results show the influence of different process parameters on the temperature distribution in the shearing zone for a fine-grained steel and clearly illustrate the capabilities of the investigated measuring concept.