本研究首先是透過實驗來探討不鏽鋼(AISI410、AISI420、AISI630)與工具鋼(H12、A6)表面光譜放射率隨著波長、溫度、合金成份與加熱時間的變化。吾人發現：(1)波長在3μm ~ 4.8μm的範圍內，光譜放射率有隨波長增加而降低之趨勢；(2)鋼材表面光譜放射率有隨溫度增加而上升之趨勢；(3)鋼材含鉻量越高時，其表面放射率也越低；(4)鋼材在加熱4小時後，由於氧化層成長趨於緩和，以至於光譜放射率趨於穩定。
接著應用多光譜輻射測溫法(MRT)，搭配線性放射率模組(LEM)與對數線性放射率模組(LLE)來預測鋼材表面的溫度。吾人利用增加求解波長數、加熱時間、增加放射率模組中的階數等因子，來探討能否有效提升預測溫度的精確性。吾人發現：(1)增加求解波長數與加熱時間，並無法改善溫度誤差；(2)增加線性放射率模組與對數線性放射率模組中的階數，並無法有效降低溫度誤差；(3)線性與對數線性放射率模組，分別在700K與900K，可獲得較佳的溫度預測；(4)整體來看，一階線性放射率模組與一階對數線性放射率模組，對不同合金成份與溫度，預測效果最好；(5)當放射率模組越能模擬鋼材表面放射率行為，所推測的溫度誤差也越小。

In this study, experiments were first conducted to investigate stainless steel and tool steel spectral emissivity which is varied with wavelength, temperature, alloy composition and heating time. Results show that (1)the spectral emissivity increases with increasing wavelength from 3μm to 4.8μm；(2)the spectral emissivity increases with increasing temperature；(3)steel with higher chromium constituent has lower emissivity value；(4)the spectral emissivity reaches steady state after the fourth hour heating due to the surface oxidation becoming fully developed.
Multispectral radiation thermometry (MRT) with linear emissivity models (LEM) and log-linear emissivity models (LLE) were then applied to predict the sample surface temperature. The effects of wavelength number, heating time and order of emissivity models were also examined. Results show that (1)increasing either wavelength number or heating time can not improve measurement accuracy；(2)increasing order does not decrease temperature error for both LEM and LLE；(3)overall, LEM at 700 K and LLE at 900 K showed better performance；(4)the first-order LEM and the first-order LLE showed the best overall accuracy for different alloys and temperatures；(5)the better emissivity model to suitably represent the real surface emissivity behaviors, the more accurate inferred temperature by MRT.

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