Effect of material removal state on the selection of theoretical models when scratching single-crystal copper using the load modulation approach

This article presents a constant force–controlled cutting approach with two different geometries of cutting tools. The methodologies for establishing two theoretical models were proposed to quantitatively predict the required applied normal forces at the expected machined depths, which were obtained with a solution to the horizontal projection of the sample–tip contact area and the multi-edge form tip based on a generalized cutting approach, respectively. The selection of the proposed theoretical models is dependent on the two material removal states, respectively, in which one is plowing for a regular triangular pyramid and the other one is cutting chips for a single-point diamond tip. To verify the feasibility and effectiveness of the proposed theoretical models and cutting strategy, a constant normal force cutting of microgrooves was implemented on a single-crystal copper substrate, while realizing constant cutting depths. The difference between the setting normal forces and the theoretical normal forces was analyzed by comparing the experimental results and the model prediction results. The aim of the present study was to investigate the effect of the geometry of the cutting tools on the material removal state and on the selection of the theoretical models.