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本文介绍一种分段刻纹镀膜光纤温度传感器,它是用光刻法及化学腐蚀的方法在光纤包层上直接形成的。由于它不需要外部敏感元件,因此具有体积小、结构简单、稳定性好、灵敏度高和抗干扰能力强等优点,适合于温度的高速度和安全的远距离测量。这种光纤温度传感器的灵敏度由刻纹数、刻纹深度和镀层等决定。 相似文献
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应用干涉法实现光纤端面多层透明膜系反射率的测量,利用镀有反射膜的待测光纤端面,构成F-P干涉仪,根据透射光谱的自由谱宽和干涉峰的半宽值,计算出膜系反射率,可直接获得光纤端面上薄膜的真实反射率,并避免了光源波动对测量结果的影响,在用反射率为92%-98.6%的膜系所进行的实验中,测量误差小于-0.09%,分析了误差来源。 相似文献
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光学薄膜技术改善分布反馈(DFB)激光器的光谱特性 总被引:1,自引:1,他引:0
地了利用镀光学薄膜的方法来改变镀层厚度,可以有效地将原来处于双模工作的1.3±mDFB激光器变为单模工作。模式改变起主导作用的是加镀膜以激光器端面反射特性中的相移。实验表明,镀膜技术可成为改善DFB激光器单模工作的一种辅助方法。实验结果有助于理解相移对激射特性的作用。 相似文献
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《仪表技术与传感器》2015,(6)
利用液体折射率与表面等离子共振技术(SPR),研究了光纤传感器在液体中透射光功率的变化,提出了一种液体折射率光纤传感器。该传感器采用3 d B耦合器进行分光,利用输出波长范围为1 530~1 580 nm的ASE作为光源,以熔融拉锥光纤作为传感单元。利用该光纤传感器,对Na Cl溶液浓度与透射光功率之间关系的进行了实验研究。研究结果表明传感器外部介质折射率越高,光的传输损耗越大。而且在锥区外部镀膜,能够有效地提高传感器的灵敏度。 相似文献
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光纤Bragg光栅的研究 总被引:15,自引:10,他引:5
分析了光纤Bragg光栅的特性,讨论了其结构参数。通过紫外光写入的方式,在普通单模光纤上制备了光纤Bragg光栅。典型的光纤Bragg光栅在1.56μm波段的反射率达99%,带宽0.6nm. 相似文献
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提出了一种通过化学腐蚀对双包层大模场光纤进行加工,并结合放电熔接工艺制备光纤法布里-珀罗(Fabry-Perot,F-P)传感器的方法。将尺寸为20/125μm的双包层大模场光纤端面切平后在浓度为40%氢氟酸中浸泡20 min使光纤端面形成凹槽,再与端面切平的HI-1060光纤进行熔接,在熔接点处形成气泡,构成全光纤F-P腔结构,反射谱波长周期为9 nm,条纹对比度达到9. 55 dB。采用等强度梁对传感器的应变特性进行测试与分析,在0~350με范围内分别进行加载与卸载实验,波长灵敏度大于2. 88 pm/με,线性度高于0. 99。 相似文献
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镁及其合金表面综合防护性差,表面强化处理成为镁制品加工业中不可或缺的重要环节,化学镀因其众多技术优势在轻合金的表面改性中具有重要地位,但经典的化学镀工艺存在工序繁杂、毒性大、成本高等诸多弊端,针对镁合金化学镀工艺技术中存在的主要问题,对镁合金化学镀展开以低污染、低成本为主要目标的研究。结果表明,改变现有化学镀的镀前处理方式,同样可以实现化学镀镀层的顺利生长,从而以更加环保的方式,在镁合金表面获得致密、光滑、均匀的合金镀层。 相似文献
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Adopting the sidewall-insulated hollow electrode (SIHE) is an ideal approach to achieve electrolyte-refresh and stray corrosion inhibition functions in micro electrochemical machining (ECM) processes. Most of the traditional SIHEs are made of metal substrate and non-metal thin films. The insulating film has poor durability, and the preparation approach of the traditional SIHE is complex and has limited repeatability. This research presents a novel structure of a SIHE with an insulated substrate and an internal conductive film. The machining performance of the novel SIHE is primarily verified by a potential distribution analysis in the numerical simulation. According to the concept of the novel SIHE, a silver-plated glass tube electrode (SPGTE) is presented: the glass tube acts as the insulated substrate, and the plated silver layer acts as the working cathode. Then, a fabrication process for the SPGTE is proposed. Silver layers are tightly bonded on the glass tube surface by electroless plating. The thickness of the silver layer is approximately 3.5 μm, and its electrical resistivity is approximately 5 × 10−5 Ω cm. In micro ECM experiments, microstructures with steep sidewalls with taper angles of <5° are machined, which is attributed to the stray corrosion inhibition of the insulated substrate. Micro holes with an aspect ratio of approximately 3 are machined. There is no accumulation of electrolytic products and short circuits, which verifies the excellent electrolyte-fresh performance. Compared with the traditional SIHEs, the novel SIHE could provide a simpler and more reliable way of fabricating sidewall-insulated electrodes. The proposed electrode structure can further inspire new electrode preparation schemes based on new substrate materials and film preparation approaches. 相似文献
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研究航空航天设备维修中应用Ni-P合金化学镀表面技术,该技术可以大量恢复设备及其零部件的性能,延长使用寿命,降低维修费用,节约原材料,减少环境污染. 相似文献
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The tribological behaviour and wear mechanism of Ni-P-Gr (graphite)-SiC (manufactured by electroless plating) is surveyed in this paper. The worn surface, wear debris and the compositional changes that take place during wear were characterized using scanning electron microscopy (SEM) and energy-dispersive analysis of X-ray (EDAX). By comparison with Ni-P-Gr and Ni-P-SiC, the results indicate that hybrid Ni-P-Gr-SiC composite presented well anti-friction and wear resistance which is resulted from a graphite-rich mechanical mixed layer (GRMML) formed on the contact surface. Hard SiC particles mixed with GRMML played a load-bearing role at high load when relative motion occurs. After heat treatment at 400 °C for 1 h, the wear rate of the hybrid composite decreased with an increase in microhardness. During sliding, the temperature of the hybrid composite occured less change than Ni-P-SiC coating and further guaranteed the stable state of the whole wear process. 相似文献
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研究了介质中NaOH浓度、镀层Cr2O3含量及热处理条件对低磷N i-P-Cr2O3化学复合镀层耐磨蚀性的影响,并与N i-P化学镀层进行了对比。结果表明:镀层的耐磨蚀性与介质中NaOH浓度呈线性关系,在任何NaOH浓度下复合镀层的耐磨蚀性均优于N i-P镀层;镀层Cr2O3质量分数在8%左右耐磨蚀性达到最佳值;经适当的热处理可显著提升镀层的耐磨蚀性。 相似文献
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在快速原型熔融沉积产生的ABS零件芯模上,采用化学镀技术,镀覆一层Ni-P/PTFE合金层.使得利用零件芯模硅胶注塑和电铸成形,得以顺利、高效地进行. 相似文献