本研究以5052-H32鋁合金為實驗材料，選擇對接接頭，進行惰氣鎢極電弧銲接(TIG銲)，對於鋁合金銲接結構件在等負荷振幅及變動負荷振幅下之疲勞性質及疲勞壽命分析模式進行深入研究。 研究結果顯示TIG銲疲勞試片斷裂點大部分是在銲道上且靠近熱影響區的位置。5052-H32 TIG對接銲件之疲勞強度(S-N曲線)比IIW、BS8118及Eurcode 9等規範之對應的設計曲線高。IIW規範之設計曲線與實驗結果最接近，尤其是在低壽命區域。在高壽命區域，各規範的設計曲線也越保守估計。綜合拉張平均應力歷程(TRN歷程)及輕微壓縮平均應力歷程(BRK歷程)變動振幅疲勞測試結果，建議以Gerber法進行平均應力修正，可得較佳的疲勞壽命預測。5052-H32鋁合金TIG對接銲件在固定振幅疲勞及變動振幅疲勞斷面上皆有疲勞紋產生。 In this study, 5052-H32 aluminum alloy weldment with butt joint were produced by inert gas tungsten arc welding (TIG welding). The fatigue properties of welded aluminum structures under constant and variable amplitude loadings were obtained, respectively. The results showed that fracture points of TIG fatigue specimens were mostly at the weld near the heat affected zone, tungsten inert gas welding the fatigue strengths (S-N curves) of 5052-H32 aluminum butt joints were higher than those of design curves proposed by IIW, BS8118 and Eurocode 9 standards. In the short life region, the IIW design curve was the best one which is close to the present experimental results. In the long life region, all the design curves of specifications were more conservative. With respect to mean stress correction in fatigue life prediction, Gerber method is the best one for 5052-H32 aluminum TIG butt joints. Both of constant amplitude fatigue loading and variable amplitude fatigue loading produce fatigue striations infracture surfaces.
