Recovery of Ti-N Powder Produced from Ti Based FRM by Reactive Gas Atomization Process by using Laser

摘要

In order to recover Ti as TiN powder from Ti based Fiber Reinforced Metal (FRM) scrap for recycling, the reactive gas atomization process by using laser was investigated. A double tapered nozzle was effective to atomize the melted TiN produced by the interaction of Ti and N2 gas, and favorable spray was accomplished.Consequently, Ti as matrix was converted to TiN by reacting with N2 gas, the melted TiN was atomized by high pressure N_2 gas, and atomized droplets were rapidly cooled on a dryice. Color of powders was gold or brown, and the shape of powders was oval or spherical, and the size of powder was in the range from several tens of #mu#m to several hundreds of #mu#m. Such an eutectic crystal or an equiaxed crystal was seen in the microstructure through an optical microscope.By X-ray diffraction pattern analysis and Electron Probe X-ray Micro-Analyzer-Energy Dispersive X-ray Spectroscopy (EPMA-EDX), it was found that the microstructure consisted of TiN_(0.7)CO_3, Ti_5Si_3 and TiN_(0.3), and Ti based FRM after laser irradiation presented a similar microstructure.