CAJ | 학술논문

通过对2219-T6铝合金搅拌摩擦焊对接接头进行金相观察、疲劳试验和显微硬度测量，对接头的不均匀性和疲劳性能进行分析。结果表明，接头最低硬度和疲劳源基本都在热影响区。基于接头各区的显微硬度、微观形貌及微拉伸试验测试，建立接头的弹塑性有限元模型，并在循环加载下模拟接头的应力和应变分布。利用Smith?Watson?Topper 损伤公式和性能薄弱区域的应力、应变数据对焊接接头进行疲劳寿命预测，预测结果与试验结果相比，寿命误差基本在两倍因子之内。
통과대2219-T6려합금교반마찰한대접접두진행금상관찰、피로시험화현미경도측량，대접두적불균균성화피로성능진행분석。결과표명，접두최저경도화피로원기본도재열영향구。기우접두각구적현미경도、미관형모급미랍신시험측시，건립접두적탄소성유한원모형，병재순배가재하모의접두적응력화응변분포。이용Smith?Watson?Topper 손상공식화성능박약구역적응력、응변수거대한접접두진행피로수명예측，예측결과여시험결과상비，수명오차기본재량배인자지내。
The inhomogeneity and fatigue properties of the friction stir welded butt joints for 2219-T6 aluminum alloy were analyzed by metallographic observation of different zones, fatigue tests and micro-hardness measurement. The results show that the lowest hardness and fatigue crack initiation sites are mainly located in heat affected zone. The elastic-plastic FE model was established based on the micro-hardness, microstructure and the mechanical properties obtained from micro-tensile tests of every zone. The stress and strain distributions of joints were simulated under cyclic loading. According to the FE simulations results, the fatigue lives were estimated by using the damage equation of Smith?Watson?Topper and the stress?strain data of the weak area in the joints. The results of estimations are compared with the test results and the errors are less than two times of factors.