Narrow Results

In this paper, a piezoelectric accelerometer with different micromechanical structures is studied, in which the micromachined silicon mass block and cantilever, covered with ZnO piezoelectric thin films, are used as the sensing element. Starting from the mechanics theory, we design the structure of sensing element and then analyze the factors affecting the sensitivity of the microdevice, including the length and width of the cantilever, the thickness of both ZnO piezoelectric thin film layer and silicon cantilever. Furthermore, finite element method in ANSYS is used to make a 3-D analysis of the microaccelerometer, the resulted resonant frequency of the fundamental mode and higher order modes, which determines the device working bandwidth, and device sensitivity are presented in the end.

The deposition using cold gas dynamic spraying of Zinc oxide/Titanium (ZnO/Ti) composite have been fabricated on Al 6061 substrate, their biocompatibility and antibacterial properties were studied. Osteoblast cell was used for the biocompatibility test while Escherichia coli (DH5α) was employed in antibacterial study. The ratios of ZnO to Ti in their composite powders were 20:80, 50:50 and 80:20 (weight %). The ZnO/Ti coatings were successfully deposited using cold spraying parameters of 13-15 Bars under helium gas, temperature of between 300-400°C. The results obtained showed that the ZnO/Ti coatings exhibited significant antibacterial effects against E. coli. Moreover, biocompatibility results reported that cell viability decreased with increasing of ZnO concentration in coating composition.