Development of ceramic coatings on aluminium and plastics by laser pyrolysis of particle filled silazanes

通过激光热解颗粒填充硅氮烷在铝和塑料上开发陶瓷涂层

• 批准号: 405583003
• 负责人: Dr. Günter Motz
• 金额: --
• 依托单位: Lehrstuhl für Keramische Werkstoffe
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/405583003?language=en
• 关键词: Development; ceramic; coatings; aluminium; plastics

In the recent years it has been shown, that the precursor technology is suitable for the preparation of ceramic coatings by pyrolysis in a furnace. However, the required high temperatures for the preparation of the ceramic coatings only allow the use of substrates with high melting points. Recently, it was demonstrated by us, that laser pyrolysis is also suitable for the formation of ceramic coatings on steel substrates. The specific input of laser radiation as the source of energy should lead to a reduction of thermal stresses of the substrate, thus enabling the preparation of ceramic coatings on substrates with low melting points. However, first tests with laser irradiation on coatings applied on an aluminium substrate showed, that the coefficient of thermal expansion (CTE) as well as the thermal conductivity have a strong influence on the process. A higher thermal conductivity leads to a faster heat dissipation. Furthermore, a high difference between the CTEs of the substrate and the coating increase the stresses generated. These problems lead to the delamination of the coating during or immediately after the laser pyrolysis. Thus, coating systems, which were successfully applied onto steel are not easily applicable to aluminium and magnesium, whereby a more intense research will be needed. For these reasons, coatings should be specifically developed for the laser pyrolysis on aluminium and subsequently on magnesium substrates within the scope of this project. Therefore it is necessary to vary the composition of the coatings as well as the process parameters systematically and to investigate their influence on the properties of the resulting coating. The next ambitious stage of development concerns the preparation of precursor-based-ceramic coatings by laser pyrolysis on plastic substrates. Until now, none of such activities have been described in the literature. In addition, plastics show an even lower thermal stability, very high CTEs and low thermal conductivity. Moreover, the resulting reduced heat dissipation during the laser pyrolysis can lead to an undesired increase of the substrate temperature. As the expected problems cannot be solved at once, coatings for carbon fiber reinforced plastics shall be developed at first and afterwards for pure plastics. For all coating systems the characterization of the most important mechanical and physical properties as well as the chemical resistance will be performed. Therefore, fundamental knowledge should be obtained, to enable a systematic development of ceramic coatings for different substrates, based on the coating composition and the process parameters to be determined.

近年来的研究表明，前驱体技术适用于炉内热解法制备陶瓷涂层。然而，制备陶瓷涂层所需的高温只允许使用具有高熔点的基材。最近，我们证明了激光热解也适用于在钢基体上形成陶瓷涂层。激光辐射作为能量源的特定输入应导致基底的热应力降低，从而使在低熔点基底上制备陶瓷涂层成为可能。然而，对应用于铝基板上的涂层进行激光照射的第一次测试表明，热膨胀系数（CTE）和导热系数对该过程有很强的影响。热导率越高，散热越快。此外，基材和涂层的cte之间的较大差异增加了产生的应力。这些问题导致涂层在激光热解过程中或之后立即分层。因此，成功应用于钢的涂层系统不容易适用于铝和镁，因此需要更深入的研究。由于这些原因，在本项目范围内，应专门开发用于铝和随后的镁基材激光热解的涂层。因此，有必要系统地改变涂层的组成和工艺参数，并研究它们对所得涂层性能的影响。下一个雄心勃勃的发展阶段是通过激光热解在塑料基材上制备基于前驱体的陶瓷涂层。到目前为止，文献中还没有描述过这些活动。此外，塑料表现出更低的热稳定性，非常高的cte和低导热性。此外，激光热解过程中所导致的散热减少会导致衬底温度的不希望的增加。由于预期的问题不能立即解决，因此应先开发碳纤维增强塑料涂料，然后再开发纯塑料涂料。对于所有涂层系统，将进行最重要的机械和物理性能以及耐化学性的表征。因此，应该获得基础知识，以便根据涂层成分和待确定的工艺参数，系统地开发适用于不同基材的陶瓷涂层。