利用微小电阻测量法测量金属丝的杨氏模量  

Measurement of Young s modulus of metal wires by using micro-resistance

作　　者：汤洁阳 吕美昱 王一凡 杨嘉旭 周留柱[1] TANG Jie-yang;LYU Mei-yu;WANG Yi-fan;YANG Jia-xu;ZHOU Liu-zhu(School of Physics and Engineering,Qufu Normal University,Qufu,Shandong 273165,China)

机构地区：[1]曲阜师范大学物理工程学院,山东曲阜273165

出　　处：《大学物理》2024年第2期68-70,78,共4页College Physics

基　　金：山东省本科教学改革研究项目(No.Z2022117)资助。

摘　　要：根据弹性模量与金属丝电阻微小变化量之间的关系式以及微小电阻测量原理,本文设计了可以测量并实时在线显示金属丝杨氏模量的实验装置.当金属丝被拉伸而引起电阻微小变化时,经过两级集成运算放大电路放大、模/数转换、单片机采集、计算后,在显示屏上就可以实时显示杨氏模量的大小.利用本装置测量了直径为0.201 mm的钢丝和直径为0.269 mm的康铜丝,其测量数据和数据处理结果表明,此杨氏模量仪测得的金属丝杨氏模量具有不大于0.3%的相对误差,精度高,且操作简单、测量时间短,为快速测量金属丝杨氏模量提供了一个可行的方法.Based on the principle of tiny resistance measurement and the relationship between the modulus of elasticity and the tiny change in the resistance of metal wire,an experimental device is designed which can measure Young s modulus of metal wire and display its value online in real time.When the metal wire is stretched,a small change of its resistance is caused.The magnitude of Young s modulus can be displayed in real time after being amplified by a two-stage integrated operational amplifier circuit,analog/digital conversion,microcontroller acquisition and calculation.The data measured on a steel wire of 0.201 mm in diameter and a constantan wire of 0.269mm in diameter show that the Young s modulus of the wire measured by this device has a relative error of no more than 0.3%.It provides a feasible method for rapid measurement of Young s modulus of wires with high accuracy,simple operation and short measurement time.

关 键 词：杨氏模量 微小电阻 金属丝 四端引线法 

分 类 号：O4-34[理学—物理]