Define specific energy for plane strain machining (cutting). In plane-strain machining, the two main sources of energy dissipation are deformation along the shear plane (~70%) and friction at the tool-chip contact along the rake face (~30%). Consider machining of a rigid perfectly-plastic work material whose uniaxial yield stress is 700 MPa, and is independent of strain rate and temperature. A tool of zero-degree rake angle is employed. Measurements showed the (deformed) chip thickness to be twice that of the undeformed chip thickness. Based on the aforementioned distribution of energy, estimate the specific energy for this process.

Define specific energy for plane strain machining (cutting). In plane-strain machining, the two main sources of energy dissipation are deformation along the shear plane (~70%) and friction at the tool-chip contact along the rake face (~30%). Consider machining of a rigid perfectly-plastic work material whose uniaxial yield stress is 700 MPa, and is independent of strain rate and temperature. A tool of zero-degree rake angle is employed. Measurements showed the (deformed) chip thickness to be twice that of the undeformed chip thickness. Based on the aforementioned distribution of energy, estimate the specific energy for this process.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Draw the forces and angles involved in the cutting process and calculate shear angle (0), friction coefficient and tangential force if ,cutting force = 80 kN, resultant of forces =100kN, friction force=75kN, rake angle =20° undeformed chip thickness = 0.65mm and deformed chip thickness = 0.72mm
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