President, Inventive Engineering, Oregon, IL
Pages: 28 Published: Jan 1986
The purpose of this development project was to precalculate forging forces. This is important not only to design the most economical machine to do the job, but also because knowledge of the exact forging force enables us to carry out the desired metallurgical change in the material.
While the work on strength, work hardening, the effect of speed on the virtual strength of the material, temperature, and friction offers little novelty and serves mostly as a summary, the formulas developed are still the results of a new and independent theoretical and experimental work; emphasis was put on developing a theory to calculate shear resistance offered by the forge material because the author found no publication dealing with this subject in spite of the fact that such forces by shear characteristically range around one third of the total forging force requirement.
The author faced the difficulty that all regular (bidirectional) shear formulas are strongly restricted in their range of validity, and, if this limited range is exceeded, the formulas suffer greatly in accuracy. Therefore, the author briefly explains existing shear theories and their ranges of validity and gives new and revised formulas for the ordinary bidirectional shear that no longer are restricted by location thickness, or by other dimensions of the material. Then the author uses the newly developed general shear theory, converting the theory to monotool shear calculation as is the case in forging.
Bauschinger effect, bidirectional shear, new and improved shear theory, shear stresses, duality principle, shear theories, forging experiments, monotool shear, friction increasing virtual strength, shear from bending, basic strength of material, shear resistance of the forge material, synthesis of forging forces, temperature effect on strength, work hardening
Paper ID: STP17375S