本研究採用SA209-T1、SA213-T22、SA213-T91鍋爐用鋼於600○C進行8、32、48小時之高溫空氣氧化、單純燃燒生質炭、單純然燒煤粉，以及混燒不同比例生質炭/煤的高溫腐蝕試驗。在8小時的間隔下持續補充燃料，模擬高溫鍋爐的煙道區域，針對燃料飛灰、氣氛的高溫腐蝕行為進行研究。藉由金屬損失量測、OM觀察、SEM、XRD、EPMA定性定量分析顯微結構形貌變化及腐蝕趨勢，比較三種鋼料的差異，以探討燃料的種類、鋼料成分對腐蝕行為的影響。
實驗結果顯示，鋼料在兩種燃料之氣氛下皆受燃料內硫成分影響發生硫化。鋼料在單純煤粉氣氛下均受到較嚴重的硫化，且在皮膜/基材界面處形成硫化物，硫化物的生成導致形成的皮膜在冷卻過程嚴重剝落，使鋼料缺乏保護性。在氣氛和飛灰的狀態時，腐蝕物質鉀元素的危害較低，硫、氯則以氣氛化合物的形式釋放，在初始階段附著在鋼料表面和以氣氛化合物的形式滲透入皮膜。隨著生質炭的比例增加，三種鋼料的金屬損失量逐漸減少。不含Cr元素之T1無論在任何情況下，皆有較大之金屬損失量。

The purpose of this study is to simulate the boiler for high temperature application to study the high temperature corrosion problems of boiler steel by fuel fly ash. SA209-T1, SA213-T22 and SA213-T91 were used as the experimental material in this study. We observe boiler steel after 8, 32, 48 hours in different fuel atmosphere at 600℃. Simulate environment include 100% coal, 20% biomass, 100% biomass and pure air condition. We continue to supply fuel per 8 hours. The results were analyzed by metal loss, OM observation, SEM/EDX and X-ray diffraction, EPMA analyze.
The results showed that boiler steel were sulfurized in fuel atmosphere. the most serious situation be happen in coal condition. Sulfur be found that existence in substrate / scale interface, exfoliation situation of scale be found here during cooling. Potassium is not major factor when fuel atmosphere corrosion condition, the most important element is chlorine and sulfur, the two element be released by gaseous compound. Fly ash contact boiler steel before oxide scale grow up, after scale grow up, gaseous compound pass through oxide scale to contact with steel. The metal loss decrease when biomass ratio reduce. Whatever any situation, T1 boiler steel always have maximum metal loss.

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