基于熔滴过渡模型的GMAW焊接发尘率计算

Calculation of fume formation rate in GMAW process based on metal transfer model

通过对实心焊丝的GMAW焊接时的熔滴过渡进行金属蒸发理论分析,结合"质量—弹簧"理论,建立了基于熔滴过渡模型的GMAW焊接发尘率预测模型.模型分析了熔滴过渡过程中熔滴温度和发尘率的变化,同时通过四阶龙格—库塔算法获得了熔滴过渡的频率及过渡熔滴半径等特征参数.结果表明,熔滴在焊丝端部长大阶段中的发尘率占总发尘率的大部分,熔滴温度超过2417K后,发尘率将陡升,模型计算的熔滴过渡频率与发尘率与实测数据非常吻合.

Through the analysis of the metal evaporation combined“mass-spring”theory in the GMAW with solid wire,the model of GMAW fume formation rate(FFR)was established.The changes of droplet temperature and FFR were analyzed in the process of metal transfer,while the frequency of droplet transfer,droplet radius and other characteristic parameters were calculated by fourth order Runge-Kutta method.The results show that the FFR during the growth stage of the droplet at the wire end is the most of the total FFR of parts,and will rise up suddenly with the droplet temperature increasing beyond 2 417 K.The calculating droplet transfer frequency and FFR of the model are in good agreement with the measured results.