基于光纤传感的钎焊接头形成及服役过程温度、应力应变实时定位监测

项目名称： 基于光纤传感的钎焊接头形成及服役过程温度、应力应变实时定位监测

项目编号： No.51265035

项目类型： 地区科学基金项目

立项/批准年度： 2013

项目学科： 机械、仪表工业

项目作者： 李玉龙

作者单位： 南昌大学

项目金额： 60万元

中文摘要： 将光纤传感器嵌入金属材料和结构内部或贴装在结构表面并形成传感网络，可获得金属结构的温度和应变等工作情况的细节，提高金属结构的可控性，增强金属结构的安全性。在钎焊过程中，接头金属钎料凝固过程中内部的温度场、应变和应力场数据很难直接测定，多采用数值模拟或间接测量的方法获得。针对上述困难，本项目拟在热膨胀系数差别较大的3003铝合金与304不锈钢钎焊过程中，于钎焊接头内部嵌入耐高温的金属化长周期光纤光栅和光纤布拉格光栅，采用光学低相干反射技术实时定位监测光栅波形、中心波长等特征量变化，重构焊接接头内部温度、应力和应变场演化过程；在铝钢钎焊接头内部嵌入光栅、表面钎焊贴装光栅，通过监测光栅波形变化，实时监测服役状态下钎焊接头应力应变演化情况。希望通过上述研究为钎焊接头形成过程、钎焊接头服役过程应力应变监测提供新方法，拓宽光纤光栅应用领域，推进光纤智能金属结构的研究工作。

中文关键词： 钎焊过程；应力应变；实时定位监测；光纤传感；温度场

英文摘要： The temperature and strain information of the metal materials and parts can be acquired by using the embedded or surface mounted fiber sensors in a sensing network. Thus the reliability and controllability of the metal parts and structures can be enhanced. It is very difficult to acquire the temperature, stress and strain data of the brazing filler metal solidification during brazing process. In the literatures, the temperature and strain data in a brazing process were normally acquired by using numerical simulation or some other indirect methods. A new method based on the fiber sensing technology is presented in this study in order to acquire the temperature, stress and strain information directly. The 3003 aluminum alloy and 304 stainless steel will be used as the base metals to be brazed due to the big differences of the thermal expansion coefficient. The Long-period Fiber Gratings (LPFG) and Fiber Bragg Gratings (FBG) will be embedded in the brazed joint to real time in situ monitor the waveform and central wavelength shift during the brazing process; Optical Low Coherence Reflection (OLCR) method will be used to analyze the data; the temperature, stress and strain field of the brazed joint will be reconfigured. The brazed joint will be also monitored during the service process by using the embedded and surf

英文关键词： brazing process；stress and strain；real time in situ monitoring；fiber sensing；temperature field