On the basis of theoretical analyses and calculations of high speed continuous impact force and tool notch surface temperature acted upon by burr and serrated chip edge, a notch wear model of low stress value and temp...On the basis of theoretical analyses and calculations of high speed continuous impact force and tool notch surface temperature acted upon by burr and serrated chip edge, a notch wear model of low stress value and temperature impact fatigue was established. Saw-tooth-shaped burr and fin-shaped chip edge continuously impacts the rake face and flank face at high speed and high fre-quency, which results in a V-shaped notch wear. An experiment was done to validate that the saw-tooth-shaped burr does affect the notch wear. This model can be utilized to solve reasonably many problems that cannot be explained by any other theoretical assumptions.展开更多
An advanced direct chip attaching packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct ch...An advanced direct chip attaching packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct chip attaching （DCA） packaging is adopted and this new packaged method simplifies the processes of packaging further. Simulations of the advanced DCA packaged sensor based on computational fluid dynamics （CFD） model show the sensor can detect wind speed and direction effectively. The wind tunnel testing results show the advanced DCA packaged sensor can detect the wind direction from 0° to 360° and wind speed from 0 to 20 m/s with the error less than 0.5 m/s. The nonlinear fitting based least square method in Matlab is used to analyze the performance of the sensor.展开更多
文摘On the basis of theoretical analyses and calculations of high speed continuous impact force and tool notch surface temperature acted upon by burr and serrated chip edge, a notch wear model of low stress value and temperature impact fatigue was established. Saw-tooth-shaped burr and fin-shaped chip edge continuously impacts the rake face and flank face at high speed and high fre-quency, which results in a V-shaped notch wear. An experiment was done to validate that the saw-tooth-shaped burr does affect the notch wear. This model can be utilized to solve reasonably many problems that cannot be explained by any other theoretical assumptions.
基金supported by the National Natural Science Foundation of China(No.61076071)
文摘An advanced direct chip attaching packaged two-dimensional ceramic thermal wind sensor is studied. The thermal wind sensor chip is fabricated by metal lift-off processes on the ceramic substrate. An advanced direct chip attaching （DCA） packaging is adopted and this new packaged method simplifies the processes of packaging further. Simulations of the advanced DCA packaged sensor based on computational fluid dynamics （CFD） model show the sensor can detect wind speed and direction effectively. The wind tunnel testing results show the advanced DCA packaged sensor can detect the wind direction from 0° to 360° and wind speed from 0 to 20 m/s with the error less than 0.5 m/s. The nonlinear fitting based least square method in Matlab is used to analyze the performance of the sensor.
