Si、Ti、Mo添加剂对自蔓延防护涂层性能的影响

为了提升自蔓延涂层的各项性能，拓宽自蔓延涂层的应用领域，本文实验制备了两种自蔓延防护涂层，即Al和Fe₂O₃的自蔓延铝热涂层和含有Si、Ti、Mo添加剂的低温自蔓延铝热涂层，借助X射线衍射、扫描电子显微镜等技术对不同成分涂层的组织形貌和物相组成进行了对比分析。利用显微硬度计、万能实验机、多功能摩擦磨损试验机研究了两种涂层的力学性能和摩擦性能。研究表明，添加剂使得涂层的孔隙率降低了66.7%,结合强度提高32.3%,常温下显微硬度提高17.6%,断裂韧性提高了28%,耐磨性能提高约25%。两种涂层均呈现出以Al₂O₃相为主的陶瓷层、金属过渡层与基体的3层结构，Si、Ti、Mo添加剂使得涂层中出现了SiC、TiC、MoSi₂等硬质相，且反应更为充分，结合强度、硬度、断裂韧性、摩擦性能均得到提升。

Influence of Si, Ti, and Mo additives on properties of self-propagating protective coating

In order to improve the properties of self-propagating coatings and broaden their application scope, two kinds of self-propagating protective coatings were prepared, namely self-propagating aluminothermic coatings containing Al and Fe₂O₃ and low-temperature self-propagating aluminothermic coatings containing Si, Ti, and Mo. The microstructure, morphology, and phase composition of the coatings with different components were compared and analyzed by means of X-ray diffraction, scanning electron microscopy, and other techniques. The mechanical properties and friction properties of the two coatings were studied by using microhardness tester, universal testing machine, and multi-functional friction and wear testing machine. Results showed that the additives reduced the porosity of the coating by 66.7%, increased the bonding strength by 32.3%, increased the microhardness by 17.6% at room temperature, increased the fracture toughness by 28%, and increased the wear resistance by about 25%. Both coatings showed a three-layer structure of ceramic layer, metal bonding layer, and substrate dominated by Al₂O₃ phase. Due to the Si, Ti, Mo additives, hard phases such as SiC, TiC, and MoSi₂ appeared in the coating. In addition, the reaction was more complete, and the bonding strength, hardness, fracture toughness, and friction properties were improved.