钢铸件上有时会有裂缝发现,而且这种裂缝总是成锯齿形的,甚至很不规则,裂缝的断面常呈氧化现象,这是由于受热的缘故,这样的裂缝称之为热裂。根据实际工作与实验中获得的经验中知道,在钢液刚凝固後不久的时候,铸件才开始发生热裂。热裂可分成二种:一为外在热裂,一为内在热裂。所 Cracks are sometimes found in steel castings, and the cracks are always zigzag-shaped, even irregular. The fractured section is often oxidized due to the heat, which is called a thermal crack. According to the actual work and experiment experience gained, just after the liquid steel just solidification, the casting began to crack. Thermal cracking can be divided into two types: one for external thermal cracking, one for internal thermal cracking. The