310不銹鋼的高溫循環氧化行為研究

High Temperature Cyclic Oxidation Behavior of 310 Stainless Steel

本研究探討310不銹鋼在800-1100 oC溫度範圍的高溫氧化及在反覆循環升降溫條件下熱循環氧化性質。氧化試驗是在管型高溫爐中進行，量測在不同溫度與持溫時間下的氧化增重，以了解氧化速率的變化。高溫試驗後的試片，以SEM及EDS觀察腐蝕後表面及橫截面的影像、微觀組織與腐蝕產物的化學成分。實驗結果顯示，310不銹鋼呈現拋物線擴散機制的氧化行為，氧化速率隨著持溫時間增加而降低。氧化腐蝕後的表面形貌隨著溫度及持溫時間不同而有所改變：橫截面的影像及分析結果顯示氧化層外層由Cr2O3所組成，在氧化層與基材交接處及基材內部有SiO2的內氧化情形發生。在1000 oC下10個週期的循環氧化試驗結果顯示氧化銹皮的附著性良好。

In this study, high temperature oxidation and cyclic oxidation behaviors of 310 stainless steel (SS) in the temperature range of 800 – 1100 oC were explored. High temperature oxidation tests were conducted in a tube furnace. The weight gains were measured at different time interval and at specific temperatures with various heating conditions. Post SEM/EDS examinations were also performed for surface morphology, cross-section microstructure and chemical composition analyses. The experimental results showed that 310 SS exhibits a diffusion-controlled parabolic oxidation mechanism, while the oxidation rate decreases with increasing holding time. A significant change in scale surface morphology associated with different types of oxide formation was observed. The cross-section SEM images reveal that the scales mainly exhibit a single Cr-rich oxide layer at the temperature range studied. Internal oxidation with the formation of SiO2 was also observed. Satisfactory adhesion of the scale to the substrate was found for cyclic oxidation at 1000 oC.