Synthesis of In-situ AlTi_2/TiC/AlTi_2C Hybrid Nanocomposite Coating on Ti Substrate

摘要

In the current investigation, mechanical alloying technique was utilized to produce a nanocomposite coating from elemental powders of Ti, Al and C on Ti substrate. The formation of coating during mechanical alloying was the results of repetitive cold welding and fracturing of powder particles with each other and with hard specimen surface due to ball-powder-substrate impacts. In this regard, X-ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM) and Energy Dispersive Xray Spectroscopy (EDS) were employed to investigate phase transformation, microstructural and morphological evolution. Micro hardness and roughness are also used to investigate mechanical properties of coating. The final Ti grain size after 12 h milled sample was estimated to be around 18 nm. The sample milled for different time was subjected to heat treatment at 900°C for 90 min. Nano scale AlTi2C and TiC phases were detected in AlTi2 matrix after heat treatment.