抄録
In the rapid sintering processes e.g. laser sintering, SPS, and combustion synthesis, the gases released from the powder strikingly affect the quality of the produced material. Therefore, in this paper, the gas release behavior of Fe powder was analyzed by gas chromatograph method. The gases such as CO2, CO, CH4, C2H6, and C3H8 were detected from Fe powder during the sintering process. Especially, a great volume of CO2 gas was released from the Fe powder. The carbon atom constituting these gas species might originate from the carbon contained in the Fe powder. Furthermore, the gas release behavior of the Fe powder dipped into liquid N2 and the Fe powder annealed in N2 gas atmosphere were investigated. In the treated Fe powder, the oxygen gas and nitrogen gas combined with the Fe powder as adsorption gas, solute gas and metal-gas compound. The oxygen release and the nitrogen gas release increased in the high temperature range of over 600°C. From the reaction analysis, it was guessed that these gases were caused by the dissociation reactions of the Fe3O4 and Fe4N phases with phase transformation.
