Numerical and experimental investigation of cooling time in laser micro-adjustment of two-bridge actuators

Multiple thermal cycles are necessary in laser micro-adjustment to achieve required deformations. Between two consecutive thermal cycles, a cooling time is necessary for the workpiece to cool down. This paper presents two cooling criteria including the same temperature (ST) and the room temperature (RT) for laser micro-adjustment of two-bridge actuators. The effects of the scaled geometry of actuators on cooling time are investigated numerically and experimentally for different processing parameters under the present cooling criteria. Considering the influence of material properties on cooling time, numerical analysis is conducted for stainless steel and aluminum alloy materials. The effects of the cut-out shapes of actuators are studied using experimental methods. The numerical and experimental results show that the cooling time can be saved significantly when using ST cooling criterion, especially for the material with high thermal conductivity and large heat capacity. Moreover it was found that the square cut-out actuator be the best choice for different scales if RT is applied. However, for large scales the circle cut-out actuator was found better if ST is used. (c) 2011 Elsevier Ltd. All rights reserved.