Effects of Solidification and Wetting on Flattening Behavior of Thermal Sprayed Ceramic Particles.
Effects of Solidification and Wetting on Flattening Behavior of Thermal Sprayed Ceramic Particles.
复制标题
凝固和润湿对热喷涂陶瓷颗粒扁平行为的影响。
DOI：
10.2207/qjjws.18.26
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
M. Fukumoto
中科院分区：
文献类型：
--
作者：
Yasunori Tanaka;M. Fukumoto
将几种陶瓷颗粒等离子喷涂并收集在保持在不同温度的金属平坦基底表面上。研究了颗粒/基体界面的凝固和润湿对颗粒展平行为的影响。观察到颗粒的转变温度与导热系数之间存在明显的线性关系，并且颗粒/基体界面的润湿性越差，该线的梯度越陡。该结果表明，即使在陶瓷颗粒中，当基材的温度接近转变温度时，也会在板的底部发生快速凝固。随着衬底温度的降低，飞溅溅射中的中心圆盘部分逐渐减小。当颗粒对基材的润湿不好时，通常可以观察到完全分散的碎片，例如在镀金金属基材上的氧化铝碎片的情况。因此，飞溅物的发生并不总是需要颗粒与基材碰撞时的快速初始凝固。因此，润湿似乎是热喷涂陶瓷颗粒在基材上变平的最主要因素。当润湿达到某种适度条件时，快速凝固被认为会影响颗粒的扁平化。
Several kinds of cermaic particles were plasma sprayed and collected on the metallic flat substrate surface held at various temperatures. Effects of both solidification and wetting at particle/substrate interface on the flattening behavior of the particles were investigated.The linear relation between transition temperature and thermal conductivity of the particle was clearly observed, and the worse the wettability at particle/substrate interface was, the steeper the gradient of the line was. This result indicates that even in the ceramic particles, the rapid solidification at the bottom part of the splat occurs when a temperature of the substrate is close to the transition temperature. The central disk part in the splash splat diminished gradually with decreasing the substrate temperature. Wholly scattered splat could be often observed when the wetting of the particle to the substrate was bad, like in the case of alumina splat on the gold coated metal substrate. Therefore, the occurrence of the splash splat does not always need the rapid initial solidification at collision of the particle to the substrate.Consequently, the wetting seems to be the most dominating factor in the flattening of the thermal sprayed ceramic particle on the substrate. The rapid solidification is thought to affect on the flattening of the particle when the wetting reaches to some moderate condition.