An Improved Upper-Bound Analysis of the Upset Forging of Strip and Its Application to the Cylindrical Disc Geometry.

摘要

For a Mises material with the assumption of constant shear stress friction prevailing between the forge platens and deforming solid, a two-zone velocity field has been solved by upper-bound limit analysis for the rectangular strip and cylindrical disc geometries. This velocity field resulted in a lower upper-bound (i.e. improved solution) for the strip geometry for conditions of high friction and a wide range of strip geometries. When applied to the disc geometry,however,the technique failed to produce an improved solution. Details of the analyses are provided along with results showing the domain of the improved solution for rectangular strip. Reasons for the 'failure'of the disc analysis are discussed.