A particular YSZ feedstock for very low-pressure plasma spraying (VLPPS) has been designed which can be automatically divided into less than 5 μm YSZ molten particles in the long plasma jet. Fully molten particles were deposited on the substrate at different deposition distances of 250, 350 and 450 mm, respectively. The deposition behavior of less than 5 μm YSZ molten particles were studied aiming to obtain a thin gastight YSZ coating. The flattening ratio of particles at different deposition distances and the gas permeability of YSZ coating prepared by VLPPS were investigated. The results revealed that the thickness of flattened particles was about 0.10-0.35 μm and the flattening ratio of molten particles was about 4.7. The flattened particles were bonded well with substrates and the width of vertical cracks appeared in flattened particles was 0.01-0.02 μm. The gas permeability of coatings prepared at 350 mm was 1.5 × 10−7 cm4 (gf)−1 s−1.

中文翻译：

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VLPPS 中小于 5 μm YSZ 颗粒的沉积行为研究

设计了一种用于超低压等离子喷涂 (VLPPS) 的特殊 YSZ 原料，它可以在长等离子射流中自动分成小于 5 μm 的 YSZ 熔融颗粒。完全熔化的颗粒分别以 250、350 和 450 毫米的不同沉积距离沉积在基板上。研究了小于 5 μm YSZ 熔融颗粒的沉积行为，旨在获得薄的气密 YSZ 涂层。研究了不同沉积距离下颗粒的扁平率和VLPPS制备的YSZ涂层的透气性。结果表明，压扁后的颗粒厚度约为0.10-0.35 μm，熔融颗粒压扁率约为4.7。扁平颗粒与基材结合良好，扁平颗粒中出现的垂直裂纹宽度为0。01-0.02 微米。在 350 mm 处制备的涂层的透气性为 1.5 × 10−7 cm4 (gf)−1 s−1。