engleski

MICROFORMING FRICTION IN METAL FORMING

The work carried out some analysis microforming. Microforming in metal forming the production of small dimensions in at least two axes not exceeding 2mm. Technology is microforming differs in many ways from the conventional technology of metal forming. It is well recognized that expertise, experience, and theoretical knowledge available in conventionally sized metal forming cannot be simply transferred to microforming. This is due to so-called size effects which have distinct effect on material flow, friction and other process characteristics. Today, process simulation is a standard tool in industry, applied to support process lay-out and its optimization. However, as it is based on continuum mechanics, it is size-invariant at least for cold forging. Hence, it is obvious that due to the size effects, conventional simulation cannot be applied to microforming. In this paper two approaches are presented how to model specific phenomena of microforming in particular concerning material flow and friction. These are the mesoscopic model and a combination of the general friction law and mechanical rheological model, respectively. Both models are brought together to be finally applied to a combined micro cold-extrusion process.

metalforming; microforming; friction

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