Application of Orthogonal Array on the Calculation of the Refractory Index in Multi-Component Glasses

Abstract

The “optimum firing temperature” (θ_f) of enamel frit is defined as the temperature at which the viscosity of the molten glass becomes 4000 poises. θ_fs of multi-component glasses were interpolated, measuring their viscosities by means of the counterbalance method. An orthogonal array of 3ⁿ-type was applied as the substituting means of the components among others, and the effects of each component substituting silica was calculated. Moreover, this effect can be used as the additive constant for θ_f, which also gives a base to derivate the “refractory index”. The new indices proved themselves more reasonable than those of R. R. Danielson's. The analysing method of the results of the acidresistance tests was also discussed, and the scale of the “rationality” of the acidresisting-enamel composition was given by means of the proper classification.