Analysis of some aspects of fine blanking process

Blanking is one of the advanced technologies of processing materials and manu-facturing products. Simple cutting is affected by the uneven action of plastic de-formation. This makes the cut surface irregular. Blanking methods have been im-proved and new technologies in the process of blanking have been developed. Using these technologies we easier achieve higher geometric precision and surface quality. One of these technologies is fine-blanking. The aim this of study was to investigate the mechanical properties of the material and verify the suitability of the material for the production of parts made by fine blanking and analyze the failure of ejector tool. Based on the tests performed we can conclude that material DN-C45 (12045) is not suitable for the production components made by fine blanking technology. For production of parts, we recommend to use the material C45 in modification GKZ-EW – soft annealing, fine cold rolled with globular pearlite, tensile strength 480 MPa, yield strength of 290 MPa and hardness maximum 150 HB. Based on documented microscopic breaches at ejector in etching state, we see that oxidation occurs at the point at the breach. In the present case for the assessment of cracks on the ejector, it is necessary to consider whether the thermal process was adhered.

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