SINA - Sensor integration in aluminum die casting

点击翻译按钮获取中文摘要

SINA - Sensor integration in aluminum die casting The most important technology to produce metal parts is casting. Metal parts often adopt load-bearing function and are subject to high thermal and mechanical stress at the same time. Their failure is a mayor security risk. Regarding this it seems appropriate to monitor their function by sensors. Ideally, the sensor should be embedded directly in the metal. The state of research shows the high importance of integrating sensing function in metal parts. Up to now, integrating sensor elements in metals during casting was bound to fail due to the high temperatures of casting and due to the thermomechanic stress during cooling down. The sensor elements were harmed or broken during embedding. The requested project investigates for the first time an innovative combination of sensor and casting technology. The aim is to equip metal parts with sensor function already while they are casted. Specifically, the integration of piezoresistive strain sensors in aluminum die casting is investigated. Several material combinations and technological process flows are investigated to meet the boundary conditions of very high temperature (several hundred °C) and high pressure. Numerical simulations are performed, sensor elements are processed, embedded and analyzed. The damage mechanisms are investigated. Mounting technologies for the electrical interconnection of the embedded sensor elements are developed. The embedded sensor acts as a foreign body in the material which may downgrade the mechanical strength. This effect is investigated theoretically using numeric simulation and experimentally using microscopy, micrographs, pull- and bending-test, and dynamic fatigue tests. In order to get a definite positioning of the sensors in the metal, concepts for positioning are developed. Using Finite Element Analysis, thermal and mechanical load patterns are developed and used to improve the layout of the sensor elements.