• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Conference Series no.182; International Symposium on the Science and Technology of Light Sources; 20040718-22; Toulouse(FR) >Transparent Ceramic Lamp Envelope Materials
【24h】

Transparent Ceramic Lamp Envelope Materials

机译：透明陶瓷灯罩材料

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

PCA envelopes have been vital to the widespread construction of contemporary HPS and ceramic metal halide lamps in place of quartz. Lamp scientists have constantly been searching new focused-beam light-sources using improved transparent ceramic envelopes for better energy efficiency, color properties, life, cost, and environmental renewability. Many studies in the literature aimed at producing improved lamp envelopes, involved sintering of ceramic materials to transparency for tube, window, infrared dome, and laser applications. While melt-grown single crystals such as sapphire are restricted to straight tubes, technological advancements in ceramic powder synthesis, forming, sintering and HIPing (hot isostatic pressing), have made possible a wide range of compositions (e.g. Y_2O_3, Y_2O_3-La_2O_3, MgAl_2O_4, YAG, and AlON), and shapes (cylindrical, bulgy, spherical, and elliptical), presenting significant flexibility to the designing of lamps and fill chemistry. Fig. 1 shows the transmittance windows" that have been achieved in several transparent ceramics relative to that of quartz. The significant accomplishment in the optical properties resulted from improved understanding of powder-processing-microstructure-property inter-relationships over the years. These transparent ceramics generally have in-line transmittance as high as quartz and higher than regular, translucent PCA. However, the rapid heating and cooling cycles encountered by the envelopes in lamps must be considered; a satisfactory thermal shock resistance is required. Quartz has excellent thermal shock resistance due to its low thermal expansion and elastic constant. Physical properties such as mechanical strength, elastic constant, thermal expansion, thermal conductivity, and emissivity, along with the geometry, size, and thickness of transparent ceramics are important parameters for assessing their resistance to withstand thermal shock and stresses in lamps. Additionally the corrosive nature of lamp-fill liquid and vapor at high temperatures requires that all lamp components be carefully chosen to meet the target life. Although the economics could be hard to justify a new transparent ceramic for improved performance (efficacy) in well-developed applications such as HPS lamp envelopes, the wide range of new transparent ceramic envelope materials represents opportunities for advanced light sources such as beamer and automotive headlights of new designs and fill chemistries.
机译：PCA封套对于当代HPS和陶瓷金属卤化物灯代替石英的广泛构造至关重要。灯科学家一直在使用改进的透明陶瓷外壳寻找新的聚焦光束光源，以提高能源效率，颜色特性，寿命，成本和环境可再生性。文献中的许多研究旨在生产改进的灯壳，涉及将陶瓷材料烧结成透明的灯管，窗户，红外圆顶和激光应用。尽管将熔融生长的单晶（例如蓝宝石）限制在直管中，但陶瓷粉末合成，成形，烧结和HIP（热等静压）的技术进步使多种成分（例如Y_2O_3，Y_2O_3-La_2O_3，MgAl_2O_4）成为可能，YAG和AlON）和形状（圆柱，凸起，球形和椭圆形），为灯和填充化学的设计提供了极大的灵活性。图1显示了相对于石英在几种透明陶瓷中已经实现的透射率窗口。光学性能的显着成就归因于多年来对粉末加工-微结构-性能相互关系的了解。陶瓷的在线透射率通常高达石英，并且比常规的半透明PCA高，但是，必须考虑到灯壳的快速加热和冷却循环；需要令人满意的耐热冲击性；石英具有出色的耐热冲击性由于其低的热膨胀性和弹性常数而产生的电阻，物理性能，如机械强度，弹性常数，热膨胀，导热率和发射率，以及透明陶瓷的几何形状，尺寸和厚度，是评估其耐化学性的重要参数。承受灯的热冲击和压力。灯泡填充液体和蒸气在高温下的腐蚀性质要求仔细选择所有灯泡组件，以达到目标寿命。尽管从经济学上很难证明一种新型的透明陶瓷可以在发达的应用（例如HPS灯罩）中提高性能（功效），但是广泛的新型透明陶瓷罩材料为高级光源（例如投影仪和汽车前灯）提供了机会新设计和填充化学。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号