SiO2包覆对稀土磷光粉在涂层中发光性能的影响

Enhanced Luminescence of Phosphorescent Composite with Rare Earth Phosphor Surface-coated SiO2

摘要:

摘 要: 为了防止稀土磷光粉在复合涂层中的发光猝灭，利用溶胶-凝胶法对稀土磷光粉SrAl2O4:Eu2+,Dy3+进行表面包覆，制备SiO2- SrAl2O4包覆粉体，再用冷喷涂技术在45#钢基体上制备Cu-14Al-X/SrAl2O4（未包覆/包覆）复合涂层，通过发光现象实现对涂层摩擦磨损状况的监测。采用SEM、激光粒度分析等技术对包覆粉体进行表征，再结合EDS、F97 Pro荧光分光光度计等研究和检测复合涂层微观组织、微区成分及其发光性能，探究冷喷涂过程中磷光粉的发光猝灭机理及SiO2包覆防猝灭工艺效果。结果表明，稀土磷光粉与Fe、Mn、Ni等金属元素接触以及喷涂粒子相互高速撞击是造成冷喷涂层发光性猝灭的主要原因。溶胶-凝胶法能够制备具有核-壳结构SiO2-SrAl2O4包覆粉体，形成的SiO2壳层结构较好地改善了粉体表面形貌，使得包覆粉体表面较为平整圆润，硬度明显增大，涂层组织过渡良好，发光性能更优。

Abstract:

Abstract: In order to prevent the luminescence quenching of rare earth phosphor in composite coatings, the sol-gel method was used to preparate SiO2-SrAl2O4:Eu2+,Dy3+ coated powders. The Cu-14Al-X/SrAl2O4 composite coatings were preparated on the 45 steel substrate by cold spray technology, and the friction and wear condition of the coatings were monitored by luminescence.The SiO2-SrAl2O4 powder was characterized by SEM and laser particle size analysis, combined with EDS and F97 Pro fluorescence spectrophotometer ,to study and detect coating’s microstructure, microcomponent and luminescence properties. The luminescence quenching mechanism of phosphor powder and SiO2 coating process effect of anti quenching in cold spray process were explored. The results show that contacting between rare earth phosphor and Fe, Mn, Ni elements and high speed impact of spray particles on each other are the main causes of the luminescence quenching of the cold spray coating. The preparation of SiO2-SrAl2O4 coating powder can be realized by sol-gel method, which can form the SiO2 shell structure that could optimize the surface morphology of the powder，make the powder smoothly and roundly, improve the powder’s hardness, have a good microstracture transition, get a better light-emitting property.