抄録
Process of the deteriorating mechanism of the strength has been investigated, by the aid of scanning electron microscopic photographs. Fissured structure of hardened Na-silicate coatings on sand grains were observed.
According to this results, deteriorations of strength of silicate moulds hardened by CO2 can be explained with binder links fissured by the formation of voids and by the crystallization of carbonates arising during the passage of vapors.
