特殊鋼溶液(鐵-矽-硼合金及鐵-鉻-鈷-錳-鉬高氮不鏽鋼)之靜滴法表面張力量測

Abstract

本研究之目,主要在探討氧化鋁與不同耐火材成份下，對Fe-Si-B合金及Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼之高溫接觸角與表面張力量測。為了探討Fe-Si-B合金及Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼對不同耐火材成份下所呈現的高溫潤濕行為，研究利用靜滴法(Sessile Drop Method)作為其高溫接觸角及表面張力的量測工具。由Bashforth 和Adams所提出之方程式，可繪出液滴的輪廓、並發現體積及密度量測的準確度會影響其表面張力的量測結果。量測Fe-Si-B合金及Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼的接觸角及表面張力之前，研究使用文獻的純銀作表面張力量測值，作為量測設備與方法的校正依據。本研究結果分為三個部分：(1) Fe-Si-B合金對於不同耐火材成份及粗糙度下的表面張力；(2)熱力學數據及Butler方程式計算Fe-Si-B三元合金表面張力結果(3) Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼對於單一氧化鋁耐火材的表面張力。 由研究結果發現Fe-Si-B合金及Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼的高溫接觸角及表面張力會隨著溫度的增加有下降的趨勢。Fe-Si-B合金的表面張力值不會因耐火材成份的改變而有所改變，僅有接觸角因耐火材成份及表面粗糙度的不同而有不同的潤濕行為。由Fe-Si-B合金之高溫接觸角的量測結果發現，含氮化矽成份的耐火材，其接觸角最高，單一成份氧化鋁及氧化矽的耐火材其接觸角最低，而複合型氧化鋁-氧化矽的耐材接觸角介於兩者之間。另外，由研究結果發現，表面粗糙度的增加，金屬液滴對耐火材表面的接觸角也會隨之增加。由熱力學數據及Butler方程式計算Fe-Si-B三元合金表面張力與實驗量測值比對發現，在金屬液滴完全熔化初期，其表面張力計算值與實驗量測值差異不大，但隨著溫度的增加，熱力學表面張力計算值與實驗量測值差異變大，初步推斷原因可能為界面化學反應及高溫階段時，固－液－氣三相界面線模糊所造成的實驗誤差。另外，由研究結果發現，Fe-Si-B合金隨著B含量的增加，對其表面張力有下降的趨勢，而增加C含量有降低整體表面張力的趨勢。對於Fe-16Cr-2Co-Mn-Mo-N高氮不鏽鋼的高溫接觸角及表面張力量測結果發現，隨著Mn及N含量的增加，接觸角及表面張力會有下降的趨勢，低Mn含量及低N含量的高氮不鏽鋼，有最高的接觸角及最高的表面張力值。

The purpose of this study is to investigate the high temperature contact angle and surface tension under various components of the refractories for Fe-Si-B alloys and Fe-16Cr-2Co-Mn-Mo-N high nitrogen stainless steels. The high temperature contact angle and surface tension are measured by Sessile Drop Method in this study. According to Bashforth and Adams equation, the accurate measurement of the contour droplet size and density will affect the measurement results of its surface tension. The surface tension of pure silver is measured and compare with literatures, the measured result is based for measurement calibration. This research can be discussed and divided into three parts: (1) The surface tension results under various refractories and surface roughness condition for Fe-Si-B alloys. (2) Thermodynamics data and Butler equation is calculated the surface tension of Fe-Si-B ternary alloys. (3) The surface tension of Fe-16Cr-2Co-Mn-Mo-N high nitrogen stainless steels on single high alumina contents refractory. The experimental results are shown the surface tension and contact angle of Fe-Si-B alloys and Fe-16Cr-2Co-Mn-Mo-N high nitrogen stainless steels decreases as temperature increases. The surface tension of Fe-Si-B alloys is not different with various refractories compositions and roughness. Only contact angle and wetting behavior variable and depends on various refractories compositions and roughness. The contact angle measurement results are shown that the refractories with the silicon-nitrogen-containing components have the highest contact angles, the refractories with single alumina or silica containing components have the lowest contact angles. The refractories with composite alumina - silica contacting have middle contact angles in between silicon-nitrogen-containing refractories and single alumina or silica containing refractories. The experimental results also showed that the contact angle increases as roughness increases. The thermodynamics data and Butler equation calculation surface tension results is close to measurement values when the metal is melted fully near liquid temperature. However, as the temperature increases, the thermodynamic surface tension calculation result is not close to experimental measured value, the reason might be interfacial chemical reaction and blurred solid-liquid-vapor triple interface line caused volume measured error at high temperature. Furthermore, increasing boron and carbon contents will decrease the surface tension of Fe-Si-B alloys. Increasing manganese and nitrogen contents will decrease the surface tension and contact angle of the Fe-16Cr-2Co-Mn-Mo-N high nitrogen stainless steels. The contact angle and surface tension measurement results are shown that the Fe-16Cr-2Co-Mn-Mo-N high nitrogen stainless steels with the lowest manganese and nitrogen containing components have the highest contact angle and surface tension.