異種金屬電阻浮凸銲接特性之研究

本研究係以沃斯田鐵型不銹鋼(SUS 304)、肥粒鐵型不銹鋼(SUS 430)與Kovar合金三種金屬薄板作搭接組合。以不同的電極材料、充電電壓、操作壓力與浮凸點高度進行電阻浮凸銲接。目的為探討不同種類的金屬薄板與製程參數對銲核面積與最大拉力的影響。實驗結果發現增加充電電壓提高了熱輸入量，有助於銲核的成長，在相同的銲接參數下，若使用的電極之導電率較高其銲核面積也較大，而操作壓力增加也會使銲核面積稍微上升。若充電電壓過低時，過多的操作壓力會使浮凸點未熔融前已將浮凸點壓潰，造成銲點強度的降低。而在低充電電壓60V時，由於熱輸入量不足以讓浮凸點形成熔融狀態，因此無法形成一有效的接合。銲點拉伸破斷呈現近圓形帶有新月形殘料的破斷型式，新月形的區域面積比較大，銲件能承受的最大拉力也比較高。由微硬度試驗的結果得知，以不同的製程參數進行電阻浮凸銲，其銲核硬度並未有明顯的變化。

關鍵字

電阻浮凸銲；不銹鋼； Kovar ；機械性質

並列摘要

In this study, austenitic stainless steel (SUS 304), ferrite stainless steel (SUS 430) and Kovar alloy sheets were resistance projection welded as lap joints. The process parameters were steel sheet combination in joints and test some important parameters as electrode material, charging voltage, operating pressure and projection height; on the nugget area and maximum tensile force of the welded joint were experimentally investigated. The results showed that increasing charging voltage increased heat input and therefore weld nugget growth. Also, high conductivity electrode material or increased operating pressure, nugget area could be improved significantly. If the selected charging voltage was too small, larger an electrode force was applied, caused premature mechanical collapse of the projection and thus decreased in tensile property. In 60V charging voltage, the heat input could not generate enough heat to cause melting and coalescence of the sheets forming a sound fusion joint. Fracture type was observed as crescent shape, larger area showed higher tensile force value. Vickers micro hardness results showed that the weld nugget hardness for all welding conditions did not show many differences