Research On Preparation And Properties Of TiAlSiCN Coatings

In order to meet the needs of large-scale industrial production,hard coatings with excellent comprehensive properties are very valuable.TiN,TiCN,TiSiN,TiAlN and TiAlCN have been extensively studied and applied,but their shortcomings limit their application.TiAlSiCN is expected to have the advantages of multiple coatings and adapt to more complicated working conditions.However,TiAlSiCN coating has many elements and complex structure.It is lack of deep understanding of the sputtering process,structure and properties of the coating.It is of great significance to carry out systematic research on the preparation process of TiAlSiCN coating.The purpose of this paper is to prepare TiAlSiCN coatings by RF magnetron sputtering,and to investigate the influence of process parameters on the microstructure and properties of the coatings.TiAl?50 at.%+50 at.%?alloy target,graphite target and Si targets are used for sputtering and the effects of Si content and N₂ flow rate on the microstructure and properties of TiAlSiCN coating are investigated.The microstructure of TiAlSiCN coating is nc-fcc-?TiAl??CN?/a-SiN_XC_Y nanocomposite structure.A small amount of composition changes will lead to significant changes in the structure of TiAlSiCN coating.With the content of Si or N increase,the interior of the coating was changed to amorphization.A hard TiAlSiCN coating with hardness of more than 3650 HV?10g?was prepared at N₂ 0.5 sccm,C120°and Si 15°.TiAlSi?40 at.%+50 at.%+10 at.%?alloy target and graphite target are used to target the sputtering,The effects of substrate temperature,N₂ flow rate and C content on the microstructure and properties of TiAlSiCN coating are investigated.The hardness and adhesion strength of the coating are the best when the temperature is 500?.Through microstructure analysis,the main internal phases of the coating are fcc-?TiAl??CN?and hcp-?TiAl??CN?under low N?C?content,with the increase of N?C?content,the inner crystalline phase of the coating is finally transformed into hcp-?TiAl??CN?.In addition,the adhesion strength of the coating can be improved by increasing the content of N?C?.The mechanical properties of TiAlSiCN composite coating in high temperature friction and wear tests are studied,the results show that the performance-optimized coating performs well in the friction wear test at 500°C.