动车组用LED主照明灯具寿命特性研究

LED灯具有节能环保、智能操控、响应时间短、寿命长等诸多优点,因而广泛应用于动车组等轨道交通车辆的照明系统上。但也发现部分LED灯具出现明显光衰、照度均匀性变差、频闪、异响等问题。文章通过6000 h室温点灯试验,确定光通量为灯具寿命的关键技术指标;采用Arrhenius高温加速老化方法进行加速试验及室温点灯试验,计算得到LED灯具激活能并确定了高温加速因子计算公式,由此对LED灯具进行剩余寿命特性研究,为动车组高级修修正照明指标提供理论依据。     

Research Progress of Interfacial Chemism of High Efficiency Organic Grinding Fluid for Si3N4 Ceramics

IntroductionGrinding is a most important machiningmethod for Si3N4ceramics. There is much re-searche on the grinding fluid acting as one of keyconditions in grinding, but rare on the applicationin engineering ceramics machining, especially Si3N4ceramics. Utilizing interfacial chemistry reactionmembrane can reduce friction coefficiem, and soft-en surface layer can improve the grinding efficiencyof Si3N4ceramics, which is a bran-new research di-rection. Because that the friction coefficient b…