leometwu的部落格

Iron melt rose from 12 to 34. Front metal stopped at 4. Chilling effect turned the corners of the vanes of the rotor into white iron, as shown in the following photos. White iron causes machining difficulty.  鉄水從1流向2, 然後12液面逐漸上昇到34.  在4的前鋒鉄水, 澆鑄過程中, 失溫太多, 必生白口.  Solution: overflow the under-cooled front metal. 了.                                                                                                                                                                                                     

High temp (>950 C) and long time (several hours) can disintigrate Cementite in a white iron into iron (Ferrite) and graphite. This process is called graphitization annealing. A
 B 
 C D

上: A~D 白口鑄鉄 內有大量的雪明碳鉄 (Cementite, 相). 不利於切削加工. 下: E ~H, 在>950 高溫下爐冷後,  雪明碳鉄大部份已分解成 石墨顆粒與肥粒鉄(基地).

 E
 F G H