工業科技日新月異，鋁合金的使用逐漸廣泛。異種鋁合金搭配在工業上使用已成為一種趨勢，鋁合金的銲接研究逐漸受到重視。因鋁合金本身的特性，如熱膨脹係數大、鋁合金表面容易形成氧化膜、熔點低、種類複雜，在銲接加工容易產生氣孔、變形、銲道熱裂縫以及母材熱影響區強度降低等問題，因此異種鋁材的銲接研究更顯重要。 本研究選用5083及7005兩種鋁合金，利用惰性鎢極電弧銲(TIG)，以ER5183為填料作平頭對接，然後經由銲後熱處理、拉伸試驗、微硬度測試、金相顯微組織觀察及破斷面分析，探討機械性質和微結構改變，並從中尋找銲後最適合之熱處理參數，以改善銲件之機械性質。 實驗結果顯示：5083同種鋁材銲接，在適當的銲後熱處理條件下，對銲件之機械性質影響不大，原因為5083為非熱處理型鋁合金。5083與7005異種鋁材銲接，在適當的銲接後熱處理條件下(全程熱處理)，對銲件之機械性質有提昇的作用。7005同種鋁材銲接，銲後做全程的熱處理，其熱影響區之硬度值皆可提昇至與原母材相同。 ;Because of the high specific strength and good corrosion aluminum alloys have been used extensively since the period of energy crises. Aluminum has greater thermal conductivity and larger thermal expansion than steels. Therefore, the weldability of aluminum alloys is not as good as steels. It is very important to study the weldability of dissimilar joint of aluminum alloys. The purpose of this research was to systematically study the weldability of aluminum alloys under Tungsten Inert Gas Arc Welding (TIG). The base metals used were 5083 and 7005 with filler metal of ER5183. Different post weld heat treatments of the weldments were conducted. A series of experiments including tensile test, microhardness test, optical metallography and SEM analysis were used to determine the releationship between mechanical properties and microstructures of the alumimum weldments. The experimental results indicate that there is no obvious difference between the 5083 weldments because they are non-heat-treatable aluminum alloys. Proper post weld heat treatment (full heat treatment) can increase the mechanical properties of the 5083-7005 dissimilar weldments. Post weld full heat treatment has a great influence on mechanical properties of the heat-affected zone of 7005 weldment.
