| 摘要 |
PURPOSE:To prevent the quench crack of the subject alloy by a method wherein a melting heat treatment is performed for an Mn-Al-C alloy having a specific ingredient ratio and then the alloy is cooled while applying pressure and variating the form. CONSTITUTION:The billet, obtained by casting the fused alloy composed of Mn of 68.0-73.0wt%, C of (MnX1/3-22.2)wt% and the basic ingredient of Al for the balance, is heated at the temperature of 1,100 deg.C for two hours, for example, and the melting heat treatment is performed. Then it is compressed using a press, deformed slightly while cooling it by pouring water, for example, at a cooling speed of 300- 3,000 deg.C/min in the temperature range of 830-600 deg.C. As a result, the quench crack inside the billet can be prevented. |
