抄録
The promoting effects of the third elements have been studied by many authors, and it was accepted that Si and Al are the most effective. But since it is not yet clear, which is the more effective, the promoting effect of them-was determined under same conditions up to the concentration Ca. 3%. As a consequence, it is acknowledged that Al is more effective than Si in all concentrations and that there are linear relations in log t and Si or Al-%. (t:time of graphitisation (in minutes)
