本研究以309L為銲料，利用GTAW將AISI 1015低碳鋼與AISI 304不銹鋼異質銲接，銲接件再進行600 ℃與750 ℃持溫1 ~ 240小時之高溫氧化、600 ℃ 1小時加熱1小時冷卻共85 ~ 384次之循環氧化與550 ℃之LiNO3-NaNO3-KNO3共晶融鹽250 ~ 1000小時靜滯腐蝕實驗，藉此探討銲接誘發之組織變化在高溫氧化的影響。
研究結果顯示，皮膜厚度和金屬損失量隨氧化時間之增加、溫度上升而上升，隨底材鉻含量上升而下降。HAZ晶粒粗細的改變，對高溫恆溫氧化、高溫循環氧化、LiNO3-NaNO3-KNO3共晶融鹽腐蝕沒有影響。1015低碳鋼之HAZ經高溫循環氧化後，因熱應力之影響產生片狀鐵氧化物，其面積隨著循環次數之增加而減少。

Gas tungsten arc welding was applied to join AISI 304 stainless steel and AISI 1015 low carbon steel with consumable – AISI 309L stainless steel wires. This study investigated the effect of the weldments on the high-temperature oxidation behavior. The oxidation test was performed by placement weldments at 600 ℃ and 750 ℃ for 1 ~ 240 hours. The thermal cycle oxidation of the weldments at 600 ℃ with the hold time 85 ~ 384 times was conducted. Also, the corrosion test was performed by immersing weldments in static molten LiNO3-NaNO3-KNO3 eutectic salt at 550 ℃ for 250 ~ 1000 hours.
The result shows that the weight loss and the thickness of corrosion scales of the samples were directly proportional to the corrosion time and temperature, however, were inversely proportional to the chromium content. The grain size changes were not influenced to the high temperature oxidation. The AISI 1015 was produced plate-like iron oxides, and the iron oxides area was decrease as the cycle-times was arising.

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