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研究钎焊连接微型多端口铝管和AA4343/AA3003/AA4343翅片,模拟汽车热交换器核心的微型组件,并优化钎焊条件.考虑5种工艺参数,用Taguchi法设计实验,目的是使钎焊接头的焊角尺寸最大化,因为焊角尺寸对钎焊接头的热完整性和力学性能有重要影响.采用金相显微镜测量钎焊接头的焊角长度,通过统计分析获得工艺参数的最佳值(峰值温度、保温时间、加热速率、微通道管类型和焊剂).在95％置信水平下,焊角长度的变化受钎焊峰值温度(77％)、保温时间(15％)和加热速率(7％)的影响最为显著.预测的最大焊角长度为(152±11)μm,并得到实验验证.对管-翅片接头的显微组织分析表明,峰值温度和保温时间的变化只影响焊角共晶区的大小,而对组成相的性质和成分无影响.“,”This work concerns the optimization of furnace brazing conditions for joining micro-multiport aluminum tubes and fins made with AA4343/AA3003/AA4343 brazing sheet in mini-assemblies mimicking the core of an automotive heat exchanger. Taguchi method was used for design of experiment, considering five process parameters with two levels of values. The aim was to maximize the fillet size of the brazed joints, which has an important influence on the thermal integrity and mechanical properties. Fillet length measurements of brazed joints were performed with a metallographic microscope. The statistical analysis allowed to obtain the optimum values of process parameters (peak temperature, residence time, heating rate, microchannel tube type and flux). At a 95％ confidence level, the variability of fillet length is most significantly affected by the peak brazing temperature (77％), residence time (15％) and heating rate (7％). The predicted maximum fillet length was (152±11) μm, which was corroborated by confirmation trials. The microstructural analysis of tube-fin joints showed that variations in peak temperature and residence time affect only the size of the eutectic zone of fillet formed, but not the nature or composition of the constituent phases.