| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an aluminum die casting by a low-cost cast iron die for small-lot production or trial production capable of reducing storage expenditure of old-type dies for mass production. <P>SOLUTION: Molten metal having a composition including 3.0 to 3.7% of C, 2.0 to 3.4% of Si, 0.5 to 1.0% of Mn, 0.02 to 0.20% of P, 0.08% or less of S, 0.3 to 2.0% of Cr, and 0.2 to 0.8% of Mo in terms of mass%, and Fe and inevitable impurities as the remainder is cast into a mold larger than the finishing dimensions of a die and after rough grinding machining, a decarbonized layer including fine voids opening in the surface is formed by thermal treatment. Then, the surface of the cast iron product subjected to the rough grinding machining is further cut, an oily mold-releasing agent is applied to the inner surface of the cast iron die finished to the finishing dimensions of the die, and the cast iron die members are combined to assemble a die having a cavity in a predetermined shape and after the molten metal is injected under pressure into the cavity of the die, the die is released to take the product out of the die. <P>COPYRIGHT: (C)2013,JPO&INPIT |
