Production of TiNi/MAX compact coatings, investigation of their structural, mechanical, tribological and self-healing properties

The aim of this study is to produce new generation compact protective coatings by combining TiNi/MAX films in honeycomb patterns and multilayer structures. Within the scope of this study, Ti2AlN MAX phase films were produced using the magnetron sputtering method and honeycomb patterns were etched on these films using plasma etching. Subsequently, the honeycomb interiors were filled with TiNi films to develop a dual coating system in a single layer. Additionally, multilayer films consisting of Ti2AlN and TiNi films were also produced. The structural, mechanical, tribological, adhesion, fatigue, and self-healing properties of these films were investigated. It was observed that the mechanical and tribological properties improved with the increase in the number of layers in multilayer films. The honeycomb patterned films, on the other hand, exhibited superior tribological performance, especially under high temperature conditions. In multilayer films, the increased number of layers negatively affected the adhesion properties due to the increased total interfacial stress between the layers. In honeycomb patterned films, it was determined that the R1-M2 film formed a better interface with the substrate material. The optimal temperature for the self-healing of the films was determined to be 800°C. As the layer thicknesses decreased in multilayer films, the TiNi-MAX system showed better compatibility and the healing performance of the films improved. Particularly, significant improvements were observed in the damaged areas of the R1-M2 film with a honeycomb pattern after heat treatment, and the detection of O, Ti, and Al elements clearly indicated that the Ti2AlN film possesses self-healing capabilities.