| 摘要 |
PURPOSE:To judge a quality of CV graphite cast iron exacly by measuring a cooling process of a molten metallic sample, obtaining the temp. difference between max. and min. eutectic temperatures basing on the measured result and thereby, by calculating a shape factor of graphite. CONSTITUTION:The molten metal is poured into a small size shell mold 2 to which a thermocouple 1 is fitted, the temp. decreases gradually with the lapse of time, attains to eutectic min. temp. TO, then the temp. rises and reaches to eutectic max. temp. TE and then the temp. falls again. The detected temp. of the thermocouple 1 is inputted to a computer CP to detect the temp. difference DELTAT between the temperature TE and TO, and the shape factor K of graphite is calculated by an equation K=a+b/DELTAT from the difference DELTAT. It is decided as CV graphite cast iron if K value is in 0.25-0.5 range, and as spheroidized graphite cast iron if said value is >0.5, respectively. |
