添加活性助銲劑對6061鋁合金MIG銲件影響

Abstract

本研究之目的主要在探討活性助銲劑對6061鋁合金MIG銲件之影響，實驗材料選用6061-T651鋁合金，活性助銲劑之選用分別為ZnO、CaF2、MoS2、Fe2O3、MgO、SiO2、MnO2、MoO3、TiO2、Na2CO3、NiO、MgCO3、Cr2O3等13種。銲接方法採用惰性氣體金屬極電弧銲接(Metal inert gas，MIG)來進行Flux bounded-MIG實驗。以金相實驗來觀察微觀組織，利用微硬度測定機來瞭解銲道機械性質，以實驗顯微鏡來量測銲道熔深及寛度。之後根據所量測之銲道熔深，取最佳之前四種活性助銲劑，以各50%的比例來調配成6種混合型活性助銲劑，分別為ZnO+MgO、ZnO+MoS2、ZnO+MoS2、ZnO+Na2CO3、MgO+ MoS2、MgO+Na2CO3及MoS2+Na2CO3，並探討不同的混合助銲劑對銲道熔深與深寛比之影響。實驗中發現在相同銲接參數下MoS2、Na2CO3、ZnO、MgO及MoO3 之單一型活性助銲劑，與未塗敷助銲劑試片之平均熔深1.2mm相比，能有效提升6061鋁合金之銲道熔深達36%~56%。在相同銲接參數下ZnO+MgO、MgO+MoS2及MgO+Na2CO3之混合型活性助銲劑，能有效提升6061鋁合金之銲道熔深達58%~60%。並且於熱裂敏感性實驗中發現添加ZnO、MoS2、Fe2O3、SiO2、MnO2、MoO3、TiO2、NiO及Cr2O3之單一型活性助銲劑可降低6061鋁合金之熱裂敏感性。最後應用田口方法與灰關聯分析來進行6061鋁合金Flux bounded-MIG對接最佳化參數實驗，以銲接電壓、銲槍走速、氬氣流量之三種銲接製程參數，配合不同混合比例之活性助銲劑來最佳化銲接製程參數，最佳化之參數可使6061鋁合金於Flux bounded-MIG對接時銲道平均熔深達6.18(mm)，與未最佳化且未塗敷助銲劑之對照組銲道平均熔深4.15(mm)相比提升了49%。

The purpose of this study was to investigate the effect of activating fluxes to the welding penetration of 6061 Aluminum. The activating fluxes used in the experiment were ZnO , CaF2 , MoS2 , Fe2O3 , MgO , SiO2 , MnO2 , MoO3 , TiO2 , Na2CO3 , NiO , MgCO3 and Cr2O3. Flux bounded-MIG(Metal Inert Gas) welding process was made on 6061 Aluminum with filling metals. The microstructure and morphology of the weldments were examined by the optical microscope. Furthermore, the Vickers hardness test was used to determine the mechanical properties of the weldments. According to the measurement results of the width and penetration of the weld bead. Based on the highest depth, four fluxes were selected to mix with each other using 50% weight percent each. The mixed fluxes were ZnO+MgO, ZnO+MoS2, ZnO+MoS2, ZnO+Na2CO3, MgO+ MoS2, MgO+Na2CO3 and MoS2+Na2CO3, and the fluxes were used for investigating the effect to the welding penetration and the depth to width ratio (D/W ratio). Under the same welding conditions, the results indicated that the fluxes MoS2, Na2CO3, ZnO, MgO and MoO3 did enhance the welding penetration of 6061 Aluminum by 36%~56%. Moreover, the mixed fluxes ZnO+MgO, MgO+MoS2 and MgO+Na2CO3 did enhance the welding penetration of 6061 Aluminum by 58%~60%. Finally, by employing the Taguchi Methods and Grey Relational Analysis to achieve optimized welding penetration , D/W ratio and Melting area, four major welding parameters were determined, which were welding voltage, torch moving speed, argon flow rate and the weight ratio of MgO and ZnO. The confirm experiment analysis demonstrated that the welding penetration was enhanced 49%.