A1= 波來鐵 生成溫度 alpha=(BCC, 肥粒)鐵 Ferrite: Gamma=(FCC, 沃斯田)鐵 Austenite: Gf= flake Graphite 片狀石墨 Fe3C=iron carbide 碳化鐵(化學名chemical); 雪明碳鐵Cementite(metallurgical冶金名) A1= pearlite reaction temp.
共晶: 自液相(L)同時結晶出兩個固相(石墨+鐵=灰共晶 碳化鐵 +鐵=白共晶) 共析: 自固相(S1)同時析出出兩個固相(S2+S3) : 沃斯田鐵(S1)---> 肥粒鐵 + (層片狀)Fe3C (此兩相的混合物, 冶金學名之為Pearlite, 台灣譯:波來鐵 大陸譯珠光體
灰鑄鐵(FC150~350) 片狀石墨數量越少越小, 強度越高. 波來鐵數量越高, 硬度越高. HB230~240, 波來鐵數量約100%. Grey cast iron(FC150~350): The fewer and smaller the graphite flakes, the higher the tensile strength. The higher the fraction of pearlite, the higher the hardness number.
球墨鑄鐵(FCD450~700) 石墨球化率越高, 波來鐵數量越多, 強度越高; 延伸率: 石墨球化率越高, 波來鐵數量越少, 延伸率越高. FCD 要高週淬火硬化時, 波來鐵數量要足夠 才易淬硬, 數量也要穩定, 淬後硬度才會穩定.
P<5%
白鑄鐵
Above: D-type graphite caused by enriched Ti% a distance from surface. This casting had D-type graphite + Ferritic matrix (low hardness) in the core and A-type graphite+Pearlite (higher hardness) matrix. The abrupt change of hardness (sudden loss of cutting resistance pressure) caused turning tip to chip quickly, resulting in very poor cutting tool life.
片狀石墨 3D影像
上: 300 x at 9x6.5 cm
Pearlite: 3000 X
下: S-- 史帝田鐵 --Steadite; F--肥粒鐵--Ferrite.
L : Ledeburite 粒滴斑鐵 ( 鐵 + 碳化鐵 的共晶混合物 eutectic mixture )
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