Black heart malleable cast iron and manufacturing method thereof

A black heart malleable cast iron comprising lump graphite distributed in a ferrite matrix, and a composition comprising:

• carbon of not lower than 2.0% and not higher than 3.4%;
• silicon of not lower than 0% and not higher than 1.4%;
• aluminum of not lower than 2.0% and not higher than 6.0%, which are all expressed by percent by mass;
• and
• balance iron and inevitable impurities, wherein
• the black heart malleable cast iron contains a concentration of aluminum dissolved in the ferrite matrix sufficient to improve a high temperature oxidation resistance of the black heart malleable cast iron compared to conventional black heart malleable cast iron, and
• a value of a carbon equivalent CE expressed by Equation (1) is not lower than 3.0% and not higher than 4.2%, where C denotes a content of the carbon expressed by percent by mass, Si denotes a content of the silicon expressed by percent by mass and Al denotes a content of the aluminum expressed by percent by mass:
• CE=C+Si/3+Al/8 (1).