Complementary tribometers for the analysis of contact phenomena in grinding
Résumé
The characterization of friction and tribological phenomena occurring in grinding requires reliable experimental input data. Up to now, existing test benches exhibit important limitations. Steep thermal gradients and elastic deformations of both machine structure, and rubbing elements are the main sources of inaccuracy cited in the literature. In this paper, an alternative approach is presented for the study and characterization of contact phenomena in grinding. It consists of two complementary test benches: the On-Machine Test Bench and the High Speed Tribometer. They are designed to overcome the limitations of current grinding experimental studies.
On the one hand, the On-Machine Test Bench enables accurate control of process parameters. This allows assessing the effect of the different grinding mechanisms on process forces, and specific energy. In addition, its configuration avoids steep thermal gradients; consequently, it is possible to obtain stable and accurate temperature measurements that can be directly related to process variables. On the other hand, the High Speed Tribometer enables to isolate adhesive effect because of its predominance. This test bench allows an accurate control of contact pressure and contact area. Then, adhesive phenomena can be characterized and related to process parameters using force and temperature measurements.
Experimental results obtained in both test benches are presented. A wide range of data (forces, specific energy, temperatures, wear…) concerning contact conditions in grinding can be obtained from this complementary approach.