| 摘要 |
<p>PROBLEM TO BE SOLVED: To manufacture a member made of cast iron with satisfactory efficiency and yield by obtaining a formed product capable of applying easily machining. SOLUTION: A molten metal of a cast iron containing a nitrogen scavenger previously mixed in a raw material and added through a measuring hopper 26 is cooled and solidified in a cavity mold of a mold forming device 18 to form a formed product B (first process S1). Before proceeding the cooling and solidification, a free N existing in the molten metal is acquired rapidly by the nitrogen scavenger, and consequently, a nitride is generated. The chill structure generated on the surface part of the formed product B is decomposed by applying heat treatment to the formed product B (second process S2). Finally, by applying the machining to the formed product B applied with the heat treatment, a cam shaft A as the member made of the cast iron being the completed product becomes to be obtained.</p> |
