Papers by Keyword: Chip-Breaking

Abstract: The high-pressure coolant supply cutting has attracted attention from a viewpoint of chip evacuation and tool life. In this study, the influence of high-pressure coolant supply on chip shape, cutting force and tool wear were investigated. The tests were carried out during external turning of stainless steel with cemented carbide cutting inserts. The results suggest that the length and radius of the chips got shorter with high-pressure coolant supply, especially supply pressure more than 5MPa. The cutting force was increase slightly with high-pressure coolant supply. However the thrust force was decrease. The uniform flank wear and crater wear were reduced and tool life was improved by high-pressure coolant supply.

Abstract: A comparative experimental study on the orthogonal cutting of titanium alloys by a polished tool, a tool containing a chip breaker groove, and a surface-textured tool was performed. The effects of different cutting tools on chip morphology, chip thickness, length and width of crack defects inside the chip, saw-teeth of the chip, and chip curl radius were analyzed during the cutting of a titanium alloy. Compared to chips formed by other tools, curled chip fragments formed by the surface-textured tool exhibited greater thickness and longer crack defect depths but smaller chip tooth pitches and curvature radii. The microstructural mechanisms involved in the interaction between the micro-texture surface cutting tool and the chips were analyzed by evaluating the cutting and texture parameters. The chip-breaking mechanism is that the micro-texture on the tool surface creates a sticky texture, leading to the micro-cutting and wrenching of chips, thereby increasing the magnitude of the tools work-hardening and chip-breaking effects.

Abstract: Chip control is a major problem to be solved in automated machining system. It involves a total system to produce chips that can be evacuated easily and reliably from the working zone and can be disposed of efficiently. In order to realize those, prediction of chip-breaking in machining is one of effective methods. In this paper, to predict the chip breakage systematically, the equivalent parameters concept is used. Through presenting a study of the effect of complicated groove insert equivalent parameters on chip formation and breaking, a predictive model of chip-breaking is constructed. Finally, chip-breaking experiments are made and the tested results show that differential chip-breaking point’s ratio is fewer than five percent, so it proves that the chip-breaking predictive model is reasonable.

Abstract: As machining technology develops toward the unmanned and automated system, the prediction of chip breaking is considered increasingly important, especially in continuous machining such as in cutting aluminum alloys. In this paper, chip breakers with different parameters are designed to produce chips that can be evacuated easily and reliably from the working zone. The formulation of chip up-curl radius is constructed through analyzing the chips subject to chip breaker. The predictive model of chip breaking is developed based on chip breaking conditions. Chip breaking strain is obtained by using backward-deducing method and cutting experiments. In order to verify the model, PCD tools with chip breakers are used to cut LY12, chip breaking areas are compared with those obtained from the predictive model. Results show the chip breaking predictive model is reasonable.

Abstract: The chip-breaking groove of a blade is one of the main factors influencing chip control. In this paper, we report the use of a virtual reality technique to optimize the shape of the groove on a blade according to the status of chip formation and breakage. First, by using the software, World Tool Kid, the virtual cutting systems were developed to determine the linkages between the moving parts in the machine tool and display the virtual course of chip formation and breakage. And then, the virtual reality of optimizing the shape of the turning blade groove was carried out, that is, during calculation of loci in dimensional movement and solving mathematical model of the chip breakage, by inputting the groove’s parameters and cutting conditions of the blade, and simulating the track in dimensional movement of a chip and the restricting relations between the chip and each barrier, the intersecting coordinates in dimensional points of chips and the breaking manner could be solved. For improper chip-breaking manner, by modifying the model parameters, the blade groove was recalculated until the chips could be broken with ease. Based on the shapes of chips, the shape of the blades’ groove can be optimized to get optimal shape.