本研究主要探討含硫麻田散體系416及肥粒體系430F不銹鋼在高溫熱鍛溫度模擬試驗下之表面形貌變化及化學反應之影響，並以低硫的麻田散體系410及肥粒體系430不銹鋼作為比較對照組。研究中利用在管型爐中及共軛焦掃描顯微鏡(HT-CLSM)內作為兩種試驗方式，後續並利用掃描式電子顯微鏡 (SEM) 觀察硫化物與基材間在試驗前與高溫短時間暴露後影像比較的相互關係，並輔以能量散射光譜儀(EDS)分析表面腐蝕產物的化學成分。試驗結果顯示，含硫的416及430F不銹鋼中在1050 oC、1150 oC及1250 oC且高溫大氣暴露下且分別持溫60秒、120秒及80秒，表面以硫化物作為化學反應初始成核的位置，隨著溫度及時間的增加與增長，硫化物逐漸被轉變為氧化物，並觀察到有明顯錳離子以硫化物為中心向外拓展的現象發生，推測其中一個原因為在高溫時有發生物質間的共晶反應，進而造成在熱鍛溫度範圍下提早液化有關，而原硫化物存在位置生長較快速，逐漸形成富錳的結瘤狀(nodule)組織，代表含硫416及430F不銹鋼除了表面有化學性質的變化外，也有物理性尺寸的改變；相較於低硫的410及430不銹鋼表面化學組成及氧化形貌則較為一致且均勻。
此外，在1050 oC、1150 oC及1250 oC且分別持溫一分鐘的共軛焦模擬試驗結果顯示430不銹鋼及含硫430F不銹鋼在試驗後皆能觀察到明顯晶界組織，對於含硫430F不銹鋼而言，若有硫化物富集時，晶界明顯分離並產生沿晶破裂，更是有硫化物集中於裂縫底端；410及416不銹鋼在試驗後會有板狀麻田散體組織的出現，但對於含硫416不銹鋼而言，硫化物的存在對於晶界的影響較不顯著，可能與其組織較430F複雜有關。
由上述兩種試驗方法的分析結果對其是否有液化以及發生沿晶破裂的機制更是後續值得將加以探討的課題。

In this study, we analyzed the surface morphology and chemical reaction of sulfur-containing 416 SS and 430F SS in 1050 oC to 1250 oC and short- term exposure for 60 seconds to 180 seconds, comparing with low sulfur- containing 410 SS and 430 SS. Surface morphology and chemical reaction were test in furnace and High Temperature Confocal Laser Scanning Microscopy (HT-CLSM). Scanning electron microscopy (SEM) for surface morphology examination and Energy Dispersive Spectrometer (EDS) for corrosion product identification. The experimental results showed that the surface chemical reaction start react at the sulfides. Increasing with time and temperature, manganese ion will diffuse outward around the sulfides. In HT- CLSM observe grain boundary separate phenomenon and have intergranular crack when sulfides were precipitate on the grain boundary. In addition, we can also see the sulfides were penetrated in the bottom of the crack. The mechanism of liquefaction and intergranular crack are discussed.

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