摘要
原料粉体的制备是直接影响等离子喷涂涂层结构与性能的关键技术之一。目前,制备高熵硼化物粉体的常用方法——硼热还原法存在制备周期长、产物含杂质及用于喷涂的粉体无法直接得到等缺点。本工作采用感应等离子球化(Inductive plasma spheroidization,IPS)工艺制备了喷涂用(Zr_(1/4)Hf_(1/4)Ta_(1/4)Ti_(1/4))B_(2)高熵粉体,并与两种传统粉体制备工艺进行了比较。研究表征了不同工艺粉体的形貌、内部结构以及粒径、密度等基本性能,探究了不同粉体制备工艺对高熵硼化物粉体显微结构及基本性能的影响,并验证了IPS工艺制备高熵硼化物粉体的普适性。结果表明,以商用微米级硼化物粉体为原料,通过混合-造粒-烧结-IPS工艺可制备元素分布均匀的高熵粉体,该粉体还具有表面光滑、球形形状、内部致密,且松装密度和振实密度高的特征。采用IPS工艺制备不同组元种类和含量的高熵硼化物粉体,进一步验证了该工艺具有良好的普适性。结合第一性原理计算和IPS技术的特点,深入分析了粉体组元固溶高熵化的形成机制。本工作有望为喷涂用高熵陶瓷粉体的制备提供一种新的方法。
Fabrication of feedstock powders is a critical technology that directly influences the microstructure and performance of plasma-sprayed coatings.Conventional boron thermal reduction methods for synthesizing high-entropy boride powders encounter several limitations such as prolonged processing time,impurity contamination,and inability to obtain spray-ready powders.In this work,an inductive plasma spheroidization(IPS)process was employed to fabricate(Zr_(1/4)Hf_(1/4)Ta_(1/4)Ti_(1/4))B_(2) high-entropy powders for plasma spraying in contrast to the other two traditional powder preparation routes.The morphology,internal structure,particle size distribution,density,and other fundamental properties of powders were systematically characterized.The effects of different powder fabricating processes on the microstructure and fundamental properties of high-entropy boride powders were systematically investigated,thereby validating the broad applicability of this methodology for synthesizing high-entropy boride powders.The results demonstrate that using commercial micron-sized boride powders as precursors,a hybrid process combining mixing,spray drying,sintering with IPS facilitates the fabrication of high-entropy powders with homogeneous elemental distribution.The resulting powders exhibit spherical morphology,smooth surfaces,high internal density,and high apparent/tap density.Further experiments on synthesizing different high-entropy borides with varied compositions confirm the extensive applicability of this method.The formation mechanism of high-entropy solid solutions is elucidated through first-principles calculations combined with the unique characteristics of IPS process.This work proposes a promising method for fabricating high-entropy ceramic powders suitable for plasma-spray coatings.
作者
余乐洋阳
赵芳霞
张舒心
徐以祥
牛亚然
张振忠
郑学斌
YU Leyangyang;ZHAO Fangxia;ZHANG Shuxin;XU Yixiang;NIU Yaran;ZHANG Zhenzhong;ZHENG Xuebin(College of Materials Science and Engineering,Nanjing Tech University,Nanjing 211816,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 200050,China)
出处
《无机材料学报》
北大核心
2025年第7期808-816,共9页
Journal of Inorganic Materials
关键词
感应等离子球化
高熵陶瓷粉体
硼化物
喷涂用粉体
inductive plasma spheroidization
high entropy ceramic powder
boride
powders for spray
