Preparation of Composite Particles with Multicomponent Dispersed Layer by Two Step Mechanofusion Processed

为了改善金属/陶瓷烧结材料的力学性能，制备了双层和多组分分散层复合颗粒。由于涂层颗粒在加工过程中不会与芯粒分离，复合颗粒技术可以应用于烧结和喷涂材料。采用两步机械熔接法制备了双层或基型复合颗粒。采用平均粒径为35um的不锈钢颗粒作为芯材。在第一次机械熔合过程中，采用氧化锆颗粒（0.3um）作为芯粒的初级涂层。在接下来的机械熔合过程中，使用电解铜颗粒、球形不锈钢（5um）和片状不锈钢（15um）进行二次涂层。在固结层复合颗粒表面包覆易塑性变形的铜颗粒，得到了双层复合颗粒。当具有固结层的初级复合颗粒与球形不锈钢颗粒进行机械融合时，初级氧化锆层脱落。这些剥离的颗粒然后暂时包裹在细小的不锈钢颗粒上，尽管无法获得稳定的二次复合颗粒。当具有团聚层的初级复合颗粒与片状不锈钢颗粒进行机械熔接时，初级复合颗粒的氧化锆团聚体粘附在片状不锈钢颗粒上。然后，这些复合团块再次粘附在核心颗粒上，产生具有多组分分散层的复合颗粒。

Composite particles with a double layer and with a multi-component dispersed layer were prepared in order to improve the mechanical characteristics of metal/ceramics sintered materials. Since the coating particles do not segregate from the core particles during processing, composite particle technology can be applied to sintered and spraying materials.Composite particles with double layer or with matrix type were prepared by two step mechanofusion process.Stainless particles of mean particle diameter in 35um were used as core materials. Zirconia particles(0.3um) were used for primary coating of core particles in the first mechanofusion process. Electrolitic Cu particles, spherical stainless(5um) and flaky stainless(15um) were used for secondary coating in the next mechanofusion process.1). Secondary composite particles with a double layer were obtained by coating the consolidated layer primary composite particles with copper particles which easily submit to plastic deformation.2). When primary composite particles with a consolidated layer were submitted to the mechanofusion with spherical stainless steel particles, the primary zirconia layer peeled off. These peeled particles then temporarily coated the fine stainless steel particles, although stable secondary composite particles could not be obtained.3). When primary composite particles with a agglomerated layer were submitted to the mechanofusion with flaky stainless steel particles, zirconia agglomeration of the primary layer adhered to the flaky stainless steel particles. These composite agglomerations then adhered to the core particles again, producing composite particles with a multi-component dispersed layer.