Cu/Al复合带固-液铸轧热-流耦合数值模拟及界面复合机理

Thermal-flow coupled numerical simulation and experimental research on bonding mechanism of Cu/Al composite strip by solid-liquid cast-rolling

双金属层状复合带固-液铸轧成形是集快速凝固与轧制复合为一体的短流程新工艺,为揭示固相覆层金属带材与基体熔体在双辊铸轧区内的复合机理,以d160 mm×150 mm双辊实验铸轧机为对象,利用Fluent商用软件建立Cu/Al固-液铸轧复合过程二维热-流耦合计算模型,研究铸轧速度、浇注温度、铜带厚度和预热温度对熔池流场、KISS点位置与复合界面温度分布的影响规律。Cu/Al固-液铸轧复合实验结果表明,铸轧区内固-液接触区、固-半固态粘连区、固-固轧制复合区界面结合效果呈现递进式强化规律,显示出温度和轧制压力对界面复合的重要作用,对成形工艺制定具有重要的指导意义。

Bimetallic layered composite strip with solid-liquid cast-rolling process is a new short flow technology which combined rapid solidification with composite rolling. Taking thed160 mm×150 mm experimental twin-roll caster as research object, a two-dimensional thermal-flow coupled model for Cu/Al solid-liquid cast-rolling process was established with commercial software Fluent to reveal the bonding mechanism between the solid copper strip and molten aluminum in twin roll casting zone. From the simulation results, the influences of cast-rolling speed, casting temperature, copper strip thickness and preheat temperature on the flow field in molten pool, KISS point location and the temperature distribution of bonding interface were studied. A Cu/Al solid-liquid cast-rolling bonding experiment was carried out. The experimental results indicate that the interface bonding effect is enhanced gradually from the solid-liquid contact zone to solid-mushy adhesion zone and solid-solid roll bonding zone, and the temperature and contact pressure play an important role on the metallurgical bonding effect of Cu/Al interface. It provides an important guidance to design this new forming process.