本研究針對AL-1100、AL-2024、AL-5083、AL-6061與AL-7005的鋁合金，在600K、700K與800K時，其放射率的實驗分析與利用多光譜輻射測溫法去推測溫度結果之探討，在多光譜輻射測溫法中，使用線性放射率模組(LEM)與對數線性放射率模組(LLE)，目的是為了找出各種不同情況下都適用的放射率模組。
放射率之特性可歸納為下列幾項：(1)放射率在2~4.8μm的波長範圍內，放射率是呈現波長增加而下降的趨勢；(2)放射率隨著加熱溫度上升而增加，在700K加熱至800K時，因為MgO造成金屬表面的褪色使得放射率的增加更明顯；(3)在相同溫度下不同鋁合金的放射率都有相似的分布，但在放射率數值的大小卻不相同，放射率隨溫度變化的大小取決於合金內部鎂元素成份的多寡與其氧化的程度；(4)在加熱時間兩小時後，由於氧化層成長的趨緩造成放射率的變化趨於穩定。
在多光譜輻射測溫法應用分析上可歸納成以下幾項：(1)放射率模組總體的表現上，增加波長個數並無明顯降低溫度誤差；(2)整體預測溫度的結果，以LLE表現優於 LEM；(3)多光譜輻射測溫法在預測溫度結果上，絕大部分都優於單光譜輻射測溫法；(4)提高放射率模組之階數，並無法降低溫度誤差之趨勢，在1 階、2階 LLE與1 階 LEM有較佳的推測結果；(5)在最小平法曲線性迴歸上，推論的輻射強度結果若能越貼近原始之料點的分布情形時，將有更準確的推論結果，進一步從推論出的放射率來觀察，只要推論的放射率分布行為越接近真實情況，則推測溫度也越精確。
筆者以三種推測結果較佳的放射率模組(1 階、2 階 LLE與1 階 LEM)再針對溫度、放射率數值與加熱時間等變數做比較得到以下之結論：(1)推測溫度誤差隨放射率增加而下降；(2)推測溫度誤差是隨溫度上升而下降；(3)在增長加熱時間對於預測溫度誤差之結果，並沒有改善的現象。

This study includes experimental investigation of surface emissivity and analysis of inferred temperature by multispectral radiation thermometry (MRT) for AL-1100, AL-2024, AL-5083, AL-6061, and AL-7005 at 600K, 700K, and 800K. Log-linear emissivity model (LLE) and linear emissivity model(LEM) are used to examine the MRT on aluminum surface temperature prediction. The goal of this study is to find the best MRT emissivity model which can compensate the aluminum emissivity variations and accurately infer the surface temperature.
For aluminum emissivity behaviors, (1) emissivity decreases with increasing wavelength from 2μm to 4.8μm；(2) emissivity increases with increasing temperature. Apparent increase in emissivity from 700K to 800K is contributed to the surface discoloration caused by MgO；(3) different alloys generally produce emissivity distributions that are similar in shape but not in magnitude at the same temperature. Variations in the concentration of alloying element magnesium cause different degrees of oxidation and lead to pronounced emissivity change in magnitude；(4) emissivity reaches steady state after the second hour heating due to the surface oxidation becoming fully developed.
For the examination of MRT emissivity models on aluminum, (1) increasing the number of wavelength does not improve accuracy；(2) overall, LLE show better performance than LEM；(3) multispectral radiation thermometry (MRT) is better than spectral radiation thermometry (SRT)；(4) increasing order does not enhance temperature prediction. The 1st order and 2nd order LLE, and 1st order LEM show better performance；(5) for least-squares technique, the closer the generated intensity and measured one, the more accurate inferred temperature; the better emissivity model to suitably represent the real surface emissivity behaviors, the more accurate inferred temperature by MRT.
The effects of temperature, emissivity value, and heating time are further analyzed by the three aforementioned best MRT emissivity models, 1st order LLE, 2nd order LLE, and 1st order LEM. Results show that (1) inferred temperature error decreases with increasing emissivity value；(2) inferred temperature error decreases with increasing temperature；(3) increasing heating time does not improve measurement accuracy.

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