Yellow curve = cooling curve; Aqua curve = cooling rate curve. x-axis: time in minute. 黃色曲線=冷卻曲線 水藍色曲線=冷卻速率曲線 x-軸: 時間, 分鐘. y- 軸: 溫度, C
TL = Temp. of Liquidus, Austenite nuclei first freeze out of melt, Higher TL --> Higher FC No. ; TE= Temp. of white Eutectic freezing, Austenite and Cementite freeze out at the same time. Longer TE --> Lower FC No. TL: 初晶 凝固溫度; 材質越高, TL 越高 TE:共晶 凝固溫度 材質越高 TE 時間越短 例:上: FC294, TE約1分鐘; 下: FC 094, TE 約2分鐘; 另外請注意: Tmax必須尖頂 TL才會被抓到. Tmax降到TL這段曲線的斜度很陡峭, 少了這一段, 電腦無法偵測TL. 通常高材質鐵水, 較會出現無TL的問題. 因為杯內Tmax 未能高於TL.
TL: 初晶凝核, 放熱, 短暫停止降溫; TL出現後, 材質高低就已底定. TL --> CE --> FC 所以即使共晶TE未出現 可放心出水
FC is a function of CE, which in turn, is a fuction of TL. So, as TL is detected, CE and FC will be determined by a empirical equation. FC, CE = f (TL); Tensile Strengh is determined as soon as TL is grabbed on cooling curve. Even if TE is not determined later, The FC number is still correct. Si = f (TE)
TE: 白口共晶凝固(white eutectic, triggered by a Te pill 碲葯 in cup), 降溫停頓(水平)時間長(1~2 分鐘). Si%= f (TE); TE 係用來計算Si%.再由上面的 CE=C+(Si/3)算出C%;(下圖中SiLo對應下限1.90, SiHi對應上限2.40, TE每上昇1C, Si%就少0.05%, 所以有時候TE抓錯抓到TL位置, 而TL又很高時,會發生Si為負數的情形,此時要以人為判斷. Si% is a function of white eutectic TE. TE is used to determine Si%. Then, C% is derived from CE= C+ Si/3 --> C=CE - Si/3.
下: 灰口共晶凝固 曲線TE部份呈 駝峰 形狀, TE不正確, TL正確. Below: grey eutectic solidification, a humpback portion on TE. Incorrect TE. Please be noted that even so, TL is still correct and the FC determined by TL is still correct. Do no feel panic about this. Too high a CE%, as well as too high a Ti% in iron melt, both will cause TE to look like this. 
鐵水注入杯中時, 應避免直沖感溫線, 以免感溫線燒斷. 應沿杯內壁注入 . Avoid glass tube, pour iron melt alongside the inner wall of cup, otherwise you will burn the sensor wire inside the cup.
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