Effect of Oxygen Adsorption on Oxygen Analysis of High Carbon Iron with Graphite Precipitates

概要

論文の詳細を見る
Analytical value of oxygen in a specimen containing graphite precipitates is affected by oxygen adsorption on the surface of the specimen. The quantity and some natures of the adsorption were examined. Carbon-saturated molten iron was prepared in a vacuum furnace, and was cast into a copper mould to obtain the analytical specimens. The oxygen content was determined by the vacuum fusion method. The results obtained were as follows : The surface of quenched specimen which contains about 0.4 wt% graphite adsorbs a rather constant amount of oxygen of about 0.002 cc (NTP) 0_2/cm^2. This amount does not change when the specimen has been preserved in a desic-cator for a few weeks. In the case of the specimen with 1 wt% graphite, the adsorption increases with increasing preservation time. The adsorption in a gray iron specimen is much larger than that in the quenched specimen and seems to vary remarkably with the treatment of specimen. Hydrogen adsorption is also observed, and a parallelism between the quantities of hydrogen and oxygen is obtained. It is suggested that those adsorptions are not a simple adsorption on the surface or graphite of the specimen but a formation of thin film of rust.
東北大学の論文