CVD法在喉衬上制备均匀致密钨涂层的工艺优化

Process Optimization for Preparing Uniform and Dense Tungsten Coatings on Throat Liners by CVD

摘要:

本研究对已建立的钨低压化学气相沉积（CVD）模型进行改进，使其可在常压条件下于火箭发动机喉衬表面沉积高性能涂层。研究分析了三种不同反应器结构（直管进气反应室、加装布气装置反应室、加装布气装置与引流板反应室）以及结构对反应室内流动特性、温度场、组分浓度及沉积反应的影响。数值模拟与实验结果表明，采用布气装置与引流板相结合的反应室可通过增强气体径向扩散，消除反应室喉衬处的涡流，从而显著提升流场均匀性。该优化设计不仅提高了喉衬构件表面沉积速率的均匀性，还小幅提升了六氟化钨的利用效率。本研究为高均匀性钨涂层CVD系统的设计提供了理论基础，同时为其工程化应用提供了可行方案。

Abstract:

This study optimized the previously established low-pressure chemical vapor deposition (CVD) model for tungsten, enabling its application under atmospheric pressure conditions to deposit high-performance coatings on the surface of rocket engine throat liners. The effects of three distinct reactor configurations, including a straight-tube inlet, an integrated gas distribution device, and a combination of a distribution device with a flow guide baffle, on the flow dynamics, thermal field, species concentration, and deposition kinetics of reactors were investigated. Numerical and experimental results demonstrate that the configuration incorporating both a distribution device and a baffle eliminates vortices within the liner region by promoting radial gas diffusion, thereby significantly improving flow field uniformity. This optimized design not only improves the uniformity of the deposition rate on the throat insert, but also slightly enhances the service efficiency of tungsten hexafluoride. This work provides a theoretical foundation for designing CVD systems for highly uniform tungsten coatings and offers a practical solution for their engineering application.