Grinding force is an important parameter related to a grinder’s properties including spindle power, machining strain, and grinding heat. A calculation method using experimental values of specific grinding energy has been known previously. In this paper, we focused on the shear force of grinding chips and calculated predictions of their tangential and normal forces from the physical properties of workpiece materials and grinding conditions. In the results, the tendency and magnitude of the grinding force of an actual machine and the predicted results were generally consistent with respect to the workpiece material and depth of cut. We believe that this method allows calculation of the grinding force in advance for workpiece materials and grinding conditions, contributing to reduced burden during set-up for conditions without having prior experience.

A micro slurry-jet erosion (MSE) method is proposed for the evaluation of thin coating surface strength. Surface strength is evaluated from wear patterns formed by the ejection of high-speed slurry-jets into the specimen via the MSE method. The material wear from erosion depends on the collision energy of solid particles. Thus, it is important to estimate particle velocity of the materials at collision to understand the wear mechanism. In this paper, the time series of slurry droplet behavior inside and outside the jets were acquired and analyzed using a high-speed video camera synchronized with a laser through Particle Image Velocimetry. In the results, the maximum droplet velocity was 40 m/s when the air flow rate is 30 L/min and 110 m/s when the air flow rate is 90 L/min. Additionally, there are some unmeasurable areas inside the jets due to numerous droplets within the measuring area.