Snow David E, Weeks Brandon L, Kim Dae Jung, Pitchimani Rajasekar, Hope-Weeks Louisa J
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, USA.
Rev Sci Instrum. 2008 Aug;79(8):083706. doi: 10.1063/1.2969031.
In order to address the issue of spring constant calibration in viscous fluids such as water, a new method is presented that allows for the experimental calibration of bimaterial cantilever spring constants. This method is based on modeling rectangular cantilever beam bending as a function of changing temperature. The temperature change is accomplished by heating water as it flows around the cantilever beams in an enclosed compartment. The optical static method of detection is used to measure the deflection of cantilever at the free end. Experimentally determined results are compared to Sader's method and to the Thermotune method most commonly used in cantilever calibrations. Results indicate that the new bimaterial thermal expansion method is accurate within 15%-20% of the actual cantilever spring constant, which is comparable to other nondestructive calibration techniques.
为了解决诸如水等粘性流体中弹簧常数校准的问题，提出了一种新方法，该方法允许对双材料悬臂梁弹簧常数进行实验校准。此方法基于将矩形悬臂梁弯曲建模为温度变化的函数。温度变化是通过在封闭隔室内使水流过悬臂梁时加热水来实现的。采用光学静态检测方法测量悬臂梁自由端的挠度。将实验确定的结果与萨德方法以及悬臂梁校准中最常用的热调谐方法进行比较。结果表明，新的双材料热膨胀方法在实际悬臂梁弹簧常数的15%-20%范围内是准确的，这与其他无损校准技术相当。
