Modelling of extrusion force using the surface response method

Due to the complexity of bulk metal forming processes, the establishment of theoretical models for these processes is prohibitively difficult and frequently impossible. Consequently, empirical models attained by means of experimental research are habitually used to replace the theoretical models. This paper describes the application of the surface response method in an attempt to define a relationship between the maximum extrusion force and three process parameters; namely, the conical die angle γ, die land height, h and die exit diameter, d. An extensive experimental program of aluminium extrusion was undertaken in parallel with the empirical modelling. An adequacy test was made on the analysed models to determine the accuracy with which the model predicted data obtained by experimental methods.