(一) 当钢铁被加热到了它的临界温度(Critical Temperature),它所含灰素就溶解到铁里面成为一种固体溶液(Solid Solution)。此时如果把它慢慢冷下来,炭素又析离出来,终于回复到未加热前那种比较软的波粒状态(Pearlitic)。如果冷卻是急剧的,炭素的析离就受到阻礙,结果就得到坚硬的马丁(Martensitic)状态。 (A) When the steel is heated to its Critical Temperature, the iron it contains dissolves into the iron and becomes a solid solution. At this point, if it is slowly cooled down, the carbon separates again and finally returns to the softer state of the wave before it is heated (Pearlitic). If the cooling is abrupt, the carbon detachment is hindered and the result is a Martensitic state.