Method for as-cast production of ausferritic ductile iron

The present invention discloses a method for the manufacturing of ausferritic ductile iron alloy which comprises the following steps:

(i) casting a melt of a ductile iron alloy in a mould;

(ii) solidification of the casting in the mould and subsequent cooling until the casting temperature is between 800ºC and 950ºC;

(iii) shaking out the casting at said temperature between 800ºC and 950ºC;

(iv) cooling the casting until the temperature of the casting reaches a value between 275ºC to 450ºC with a high enough cooling rate in order to avoid the pearlitic nose;

(v) introducing the casting in an insulating material and leaving the casting inside for a period of time until a completely ausferritic microstructure is obtained. The invention also discloses the ausferritic ductile iron alloy produced by the present method.