Process modeling in machining. Part I: determination of flow stress data

In the present study, two-dimensional orthogonal slot milling experiments in conjunction with an analytical-based computer code are used to determine flow stress data as a function of the high strains, strain rates and temperatures encountered in metal cutting. The workpiece materials selected for the present study are AISI P20 mold steel (DIN 1.2330, 35CrMo4) hardened to 30 HRC, AISI H13 tool steel (DIN 1.2344, X40CrMoV51) hardened to 46 HRC and Aluminum EN AW 2007 (DIN 1725 T1: AlCuMgPb, 3.1645) cold hardened to 100 HB. The methodology of flow stress determination for metal cutting, suggested in the present study, has advantages when compared with methods such as the Hopkinson's bar technique. This paper summarizes the first part of the study, conducted to estimate process variables in machining operations. The second part of the study, summarized in a different paper, addresses the application of flow stress data for predicting forces, stresses and temperatures in machining.

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