SYNOPSIS Forging tests have been made using axisymmetric cavity dies with various flash geometries.
For a particular flash geometry greater ‘rise’ was obtained with thinner flash. Also greater rise was obtained on a hammer than on a press, the load requirements being greater on the higher speed machine. Modes of metal flow were similar at all preheat temperatures. Theoretical treatment of the later stages of die filling, considering metal flow to be significant only in the region of the flash land, is able to describe the main features of the experimental results.
Get full access to this article
View all access options for this article.
References
1.
StoterH. J., ‘Untersuchung dee Schmiedevorgangs in Hammer and Presse, insbesondere Linsichtlich des Steigens’ Forschungsbericht des Landes Nordrhein - Westfalen No. 848, Koln und Opladen 1960: Westdeutscher Verlag.
2.
SiebelE.‘Die Formgebung im bilds men Zustand’ Dusseldorf 1932: Verlag Stahleisen.
3.
ScheyJ.WallaceP. W.ShunkF. A.‘Metal Flow in Closed Die Forging of Steel’, Research Reports of work at Illinois Institute of Technology Research Institute sponsored by Committee of Hot Rolled and Cold Finished Bar Producers. American Iron and Steel Institute.
4.
ViereggeK.‘Einflub des Gratspalts beim Gesenkschmeiden’, Industrie Anzeiger, 1970, 92, No. 49 pp 1119–1121.
5.
ThomsenE. G.YangC. T.KobayashiS.‘Mechanics of Plastic Deformation in Metal Processing’, MacmillanNew York1965.
6.
McDermottR. P.BramleyA. N.‘An Elemental Upper-Bound Technique for General Use in Forging Analysis’, Proc. 15th Int MTDR Conf. Sept. 1974 to be published.
7.
SchroederW.WebsterD. A., ‘Press Forging Thin Sections: Effect of Friction, Area and Thickness on Pressures Required’, J Appl. Mech.1949, 16 pp 289–294.
8.
LangeK.‘The Influence of the Dimensions of the Flash Gap on the Compression Stresses in the Gap and the Cavity and the Filling of the Die in Die Forging’, Metal Treatment and Drop Forging Sept. 1962 pp 373–380.
9.
DeanT. A.SturgessC. E. N., ‘Stress-Strain Characteristics of Various Steels Over a Wide Range of Strain-Rates and Temperatures’, Proc. I. Mech. E.1973, 18740/73 pp 523–533.
10.
DeanT. A.‘Load and “rise”; their dependence on flash geometry and machine characteristics in drop forging’. Proc. 17th Int. MTDR Conf. 1976 p. 363.
11.
DeanT. A.‘The influence of billet inertia and die friction in forging processes - a simple energy approach’. Proc. 11th Int. MTDR Conf. 1971 p. 761.
