An investigation into the behaviour of selected boundary regime lubricants when cold forging steel under rolling-sliding conditions

A study of PVD coatings, solid-in-liquid suspensions, and an ashless phosphate ester in oil at the upper die-workpiece interface when cold rotational rotary forging martensitic steel. The aim was to gain tribological insight for advanced near net-shape process development. test method a cylinder upsetting operation using industrial-scale press, lubricants were applied via in-process spraying. Forming cycle torque requirements lowest water-based suspensions employed. However, there positive correlation between friction homogeneity through-thickness deformation, oil-based dispersions generated superior surface roughness. synergism occurred MoS2 micro-platelets mixed mineral oil. This lubricant achieved higher quality finish greater protection against adhesive wear than did each component dispersed separately.