Manufacturing of lead free transparent piezoceramics by densification and crystallisation of laserfused microspheres

通过激光熔融微球的致密化和结晶化制造无铅透明压电陶瓷

• 批准号: 228897831
• 负责人: Professor Dr. Jens Günster, Ph.D.
• 金额: --
• 依托单位: Institut für Nichtmetallische Werkstoffe
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/228897831?language=en
• 关键词: Manufacturing; lead; free; transparent; piezoceramics

In vehicles and machines vibrations occur which can lead to noice emission. To reduce these effects adaptronic systems with piezoceramic actuators shall be used. At the moment piezoceramics in most cases are lead containing systems like PZT. Because of the environmental harmfulness there is big scientific interest in lead free piezoceramics. The research focus in the moment are KNN systems. Transparent piezoceramics shall be used e.g. as vibration damping systems on windows.In this proposal the development of amorphous microspheres with stochiometric composition KNN will be investigated via laser fusing. By means of a CO2 laser the starting materials will be melted and form because of the surface tension of the liquid phase microspheres. The well defined laser beam profile leads to high cooling rates which can prevend crystallisation. The microspheres will be investigated considering transparency, homogeneity, particle size as well as glass transition and crystallisation temperature. The temperature difference between glass transition and crystallisation is called kinetic window and will be used for densification of the microspheres to obtain amorphous samples with a larger volume. The crystallisation of the material will be investigated by defined temperature treatments with regard to the piezoelectric properties and the transparency of the material.

车辆和机器中会发生振动，从而导致噪音排放。为了减少这些影响，应使用带有压电陶瓷执行器的自适应系统。目前，大多数情况下压电陶瓷都是含铅系统，例如 PZT。由于对环境的危害，无铅压电陶瓷引起了巨大的科学兴趣。目前的研究重点是KNN系统。应使用透明压电陶瓷，例如作为窗户上的减振系统。在本提案中，将通过激光熔融研究具有化学计量成分 KNN 的非晶微球的开发。通过二氧化碳激光，由于液相微球的表面张力，起始材料将被熔化并成型。明确的激光束轮廓可实现高冷却速率，从而防止结晶。将研究微球的透明度、均匀性、粒径以及玻璃化转变温度和结晶温度。玻璃化转变和结晶之间的温度差称为动力学窗口，将用于微球的致密化以获得更大体积的非晶态样品。将通过关于材料的压电特性和透明度的规定温度处理来研究材料的结晶。