【作者】 孙艳；

【导师】 姜德生； 杨明红；

【作者基本信息】 武汉理工大学 ， 材料加工工程， 2010， 硕士

【摘要】 氢燃料是一种无污染的新型能源,但它存在高度的易燃性和易爆性。因此氢燃料的存储、使用和运输的过程中可能产生危险。能够提前预报氢气的泄露对保护人类生命财产安全上显得极为重要。考虑到氢气易燃,本文采用光纤作为敏感探头元件,在氢气环境下测试低于爆炸极限的氢气浓度。以微透镜型光纤氢传感器为研究对象,研究了光波在金属表面的反射与透射原理以及氢敏感膜与氢气的反应机理；在光纤端面镀制氢敏感膜,发现了氢气浓度变化与氢敏感膜材料折射率的变化存在关系。通过光学研磨、端面切割等手段对光纤端面进行加工,获得平整光洁的光纤端面。并采用高真空磁控溅射镀膜技术将敏感膜溅射在光纤端面、硅片、有机玻璃上。通过对硅片进行SEM扫描电镜扫描薄膜表面形貌、紫外可见分光光度计对玻璃片进行不同波长透过率的测试,从微观与宏观上测试敏感膜的性能。研究了单模光纤端面上镀Pd膜、W03膜、Pd/WO3复合膜的氢气传感特性。结合C8051F120单片机芯片板,通过串口将芯片板上的数据传输到电脑终端记录并保存,完成对光纤端面敏感膜的测试。通过一系列测试得出,经过改进的Pd、W03共溅射膜能够改善单一Pd在反复测试氢气的实验中出现的裂纹、脱落现象,提高了敏感膜的机械强度。通过测试不同厚度、不同材料的氢敏感膜的光强变化幅度和响应时间,可以得到敏感膜能分辨出浓度为0.01%的标准氢气,对2%-4%标准浓度的氢气响应最明显,对0.01%-2%和超过4%的标准浓度的氢气均有明显响应。通过改进薄膜厚度,响应时间可减小到15s以下,回复时间可减小到200s以下,薄膜重复性较好。另外,通过利用C8051F120单片机芯片板的数据传输功能改善了光强型氢气传感器人工记录数据的工作方式,提高了数据的精度与连续性。更多还原

【Abstract】 Hydrogen fuel is a new fuel which is non-polluting. But the character of hydrogen is highly detonable and flammable, which makes hydrogen fuel storage, use and transportation may pose a risk. Therefore, it becomes extremely important to early warn of hydrogen leaking which can protect human life and property security.Taking the flammability of hydrogen into account, in this paper, optical fiber is used as a sensing probe in hydrogen environment to test the hydrogen concentration which is below the explosive limit. Studying on micro-mirror optic fiber hydrogen sensor, by the principle of light reflection and transmission on the metal surface combined with the reaction mechanism of hydrogen-sensitive film and hydrogen, it coats hydrogen sensitive film on fiber end face. Through the relationship between the hydrogen concentration and hydrogen-sensitive film refractive index, it can research the optic fiber hydrogen sensor test system based on the principle of light reflection and transmission on the metal surface.By means of optical grinding and cutting optical fiber end face, it can access clean fiber end face. Using high vacuum magnetron sputtering system, it is coated sensitive film on the optical fiber end face, silicon, glass. Using electron microscope(SEM) to scan the surface appearance of sensitive films and using UV-Vis photometer of different wavelengths to test the transmittance of sensitive films on the glass, to test the micro and macro performance of sensitive film. It can study the properties of Pd, WO3 and Pd/WO3 hydrogen sensing film on single-mode fiber end face. C8051F120 MCU chip board transfers data to computer terminals through serial port, records and saves the test data.Through a series of tests, Pd and WO3 co-sputtered film can completely change cracks and shedding of Pd film. This film can enhance the mechanical strength of the sensitive film. By testing the intensity range and response time on different thickness and different hydrogen-sensitive film, Pd and WO3 co-sputtered film can distinguish the standard hydrogen concentration of 0.01%. But response is the most obvious in concentration of 2%-4%. There are also responses at concentration of 0.01%-2% and more than 4%. By improving the thickness of film, the response time can be lower than 15s and the recovery time can be lower than 200s. The Pd and WO3 co-sputtered film has good reproducibility. In addition, by using C8051F120 microcontroller chip board, it improves the data transmission capabilities of the light intensity-type hydrogen sensors which were manually recorded data, so the data is more accuracy and continuity.更多还原