Cylindrical cropped billets are often used in the cold forging plants at the beginning of processes and the same cylindrical billets are involved as test specimens in the proposed procedure.
On the experimental device, the specimens rotate whilst a semi-cylindrical indenter exerts a constant normal load on it. Tangential force values are measured all along the rotation time. Test adjustable parameters are the normal load exerted, specimen rotation speed and indenter radius of curvature.
The optimum values of the test parameters are defined in considering the pickup occurrence. Then, the influence of treatments parameters which correspond to different phosphate coatings and lubrication states are analyzed in terms of friction tangential force versus sliding velocities and sliding displacements.
The influence of three treatments parameters, acid pickling, phosphating bath and lubricants are enhanced by using the testing procedure for typical 1020 and 4142 carbon steel specimens. Significant tangential friction force versus sliding length curves are obtained.
The proposed test and procedure are able to determine critical friction curves and allow the secure management of both coating treatments and cold forging sequences.