Sébastien Garnier

Optimization of Process Parameters in CFRP Machining with Diamond Abrasive Cutters

The present paper proposes a methodology to optimize process parameters for trimming applications with diamond abrasive cutters. This methodology is based on the study of quality of trimmed surface, through material integrity and surface roughness, and on the study of cutting mechanisms. Their evolutions according to tool parameters and cutting conditions have been analysed. Results show that diamond grits size must be chosen according to the required surface roughness. Feedrate must respect cutting limitations due to CFRP removal mechanisms with abrasive cutters, which have been identify through analyses of specific cutting energy. Finally, a protocol in two steps is proposed to determine the optimum process parameters according to the application. Firstly, constraint functions due to respect of quality and to limiting cutting phenomena are defined. Thus, limiting values of process parameters are determined. Then, process parameters are selected in order to optimize productivity.

Investigation of CFRP machining with diamond abrasive cutters

Diamond abrasive cutters are more and more used for industrial applications of CFRP laminate machining, due to their resistance to abrasion and low cost. The objective of the approach is to improve productivity during trimming operations, by choosing adapted tools and cutting parameters. The objective of this article is to determine to what extent feedrate and spindle speed can be increased. To do so, specific cutting energy (Esp) and cutting forces are studied. Designs of Experiments and ANOVA are performed in order to analyze the influence of tool (grit size, level of nickel and diameter) and process (feed per revolution and cutting speed) parameters. It shows that high cutting speed is favourable to the cut due to thermal effects. Conversely, the study of specific cutting energy reveals that the feed increase is limited by diamond grit size and level of nickel due to the saturation of the tool intergrit space.