稀土元素對Sn-3Ag-0.5Cu-4Ti活性軟銲填料合金氧化行為之影響

Effect of Rare Earth Elements on Oxidation Behavior of Sn-3Ag-0.5Cu-4Ti Active Solder

本研究主要探討微量稀土元素添加於Sn-3Ag-0.5Cu-4Ti活性軟銲填料合金中，對填料合金在200℃及250℃的高溫大氣環境中氧化行為的影響。微量的稀土元素添加於活性銲錫合金中，明顯降低合金在200℃之氧化速率。隨著稀土元素添加量增加，氧化速率亦隨之增加。添加0.05 wt.%的稀土元素之活性軟銲填料具有最佳的抗氧化性。在銲錫熔融狀態下之250℃高溫大氣環境中，於1008小時長時間氧化，所有合金表面形成TiO氧化層均小於1.5μm。當稀土元素添加量大於0.2 wt.%時，氧化速率明顯提升。在250℃經1008小時氧化後，添加0.5 wt.%稀土元素的活性填料合金之表面形成氧化層厚度是0.05 wt.%添加量的6倍。

In this study, the effects of trace addition of rare earth elements on the oxidation behavior of Sn-3Ag-0.5Cu-4Ti active solder were investigated in air at 200 and 250 ℃. Addition of a trace amount of rare earth elements into active solder resulted in decreasing the oxidation rate of the solder at 200 ℃. The oxidation rate increased with increasing the amount of rare earth elements in the solders. The active solder containing 0.05 wt.% rare earth elements showed the best oxidation resistance. After oxidation in air at 250 ℃ under the solder melting condition for 1008 hours, a less than 1.5 μm thick TiO oxide layer formed on solder. Doping concentration more than 0.2 wt.% rare earth elements, the oxidation rate increased significantly with the amount of the rare earth elements. After an exposure time of 1008 hours in air at 250 ℃, the oxide layer formed on the 0.5 wt.% rare earth elements containing active solder was 6 times the thickness of the 0.05 wt.% rare earth elements containing solder.