A.HT200 B.HT250 C.HT300 D.HT350
A.2.2%~2.8% B.2.9%~3.6% C.3.7%~4.3% D.4.4%~4.8%
A.鐵素體+團(tuán)絮狀石墨 B.鐵素體+球狀石墨 C.鐵素體+珠光體+片狀石墨 D.珠光體+團(tuán)絮狀石墨