High-speed forming - Lubrication and friction

This document should be read in conjunction with the file which deals with the determination of a behavior law by numerical simulation.

Knowledge of friction parameters is fundamental to mastering the high-speed forming operation. The role of friction in high-speed forming processes can be positive or negative. When one of the tools is driven, as in rolling, then friction is necessary to engage and drive the product into the right-of-way. When the tool is non-driven, as in wire drawing or machining, then friction is parasitic, leading to increased stress and tool temperature, surface defects and even product breakage in wire drawing, as well as accelerated tool wear. We describe a methodology for determining a coefficient of friction between a tool and a material for different lubricants and types of loading. By using the material behavior law and a friction law, and subjecting the material to rheological tests close to forming conditions, the friction coefficient can be determined by numerically simulating the deformation test.