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Minimum quantity lubrication (MQL) has been proposed as a promising alternative to conventional flood cooling to substantially reduce the lubrication usage while maintaining high surface quality. Residual stress induced by grinding process directly affects the surface quality of the final product. An analytical relationship between residual stresses and process conditions such as process parameters, material properties, and lubrication conditions could support process planning and optimization of MQL grinding. This paper has presented a physics-based model to predict residual stresses in grinding with consideration of the lubrication and cooling effects of MQL. Grinding force and temperature distribution in the workpiece are used to calculate the loading stresses imparted by MQL grinding. The loading stresses are then coupled into a rolling/sliding contact algorithm to solve for residual stresses. Experimental measurements of residual stress profile under and flood cooling conditions have been pursued to calibrate and validate the predicted results. [ABSTRACT FROM AUTHOR]

In a free-state condition, deformable bodies (or compliant parts) have a significantly different shape than their nominal geometry (CAD model) due to gravity loads and residual stress. Typically, the dimensional metrology of such parts requires a particular approach where expensive and specialized jigs are needed to constrain and follow the component during inspection. This paper proposes a new method to fixtureless inspect deformable bodies by adapting the coherent point drift (CPD) algorithm. This new approach combines the optimization of the smoothness regularization parameters of the CPD powerful non-rigid registration method alongside the Thompson-Biweight statistical test as an identification method to distinguish profile and localization process manufacturing defects from a part's deformation. In other words, a new 'flexible' registration approach that meets the specifications of compliant parts is proposed. The CAD model is smoothly modified to fit the scanned part by minimizing two criteria that belong to deformable bodies. The first criterion is the conservation of the curvilinear distance (isometric transformation). That is to say, the condition that the stretch difference between the original CAD model and the modified one should be very small. The second criterion is the usual minimization of the Euclidean distance between the modified CAD model and its corresponding scanned part. Many case studies were performed on a typical industrial sheet metal which presented profile and localization defects. The estimated values of the defects, as well as their positions, are much closer to their reference ones in most cases, thus reflecting the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]