Liquid-Phase siliconizing method for prepare silicido-aluminide protective layers resistant to high temperature oxidation

摘要

Titanium and titanium alloys have excellent combination ratio high strength versus low density. These properties are excellent for aerospace industry. A disadvantage of titanium and titanium alloys is only high oxidation rate at temperature 600 °C and above. Liquid-phase siliconizing by Al-Si alloys was studied as a simple non expensive method for preparation of protective layers on titanium alloy. This method is based on a great affinity of silicon to titanium and has been studied by several authors. The layers have great protective effect at higher temperatures. Layers were prepared by liquid siliconizing by Al-20wt%Si. Layer is composed from ternary phase τ-2 (Ti(Al-xSi-1_x)2). High temperature resistance of layers was evaluated during oxidation at high temperature. After high temperature oxidation changes in layer composition were observed by Scanning electron microscopy and Energy dispersive X-ray analysis (SEM/EDX). Liquid-phase siliconizing was presented as simple and effective method for preparing of protective layers on titanium alloys for high temperature application of component which are not exposed to high stress application.