冷轧复合工艺对4004/3003/4004铝合金复合带组织和性能的影响

Effects of the Cold Rolling Composite Process on Microstructure and Properties of 4004/3003/4004 Aluminum Alloy Composite Strip

关键词:  冷轧复合  铝合金复合带  包覆率  显微组织  抗下垂性能  力学性能

Key words:  cold rolling composite  aluminum alloy composites strip  clad ratio  microstructure  sagging resistance  mechanical properties

摘要:

为得到最优的冷轧复合工艺参数，提高铝合金复合带的性能，并为产业化应用提供理论参考，以4004/3003/4004层状复合铝合金为对象，采用光学显微镜、扫描电子显微镜、马弗炉和万能拉伸机等仪器设备，分析冷轧复合工艺对4004/3003/4004铝合金复合带显微组织、抗下垂性能及力学性能的影响。结果表明：冷轧复合技术可以获得更均匀的复合带包覆率，且冷轧第一道次加工率为35%可使芯层和皮层材料牢固结合。冷轧复合带的抗下垂性能随着成品前道次加工率的增加先增加后降低，而随着中间退火温度变化呈相反的变化趋势，当退火温度为420℃时，复合带抗下垂性能最差。当中间退火温度为270-370℃时，冷轧复合带材的力学性能急剧下降，退火温度为370℃时复合带材的力学性能开始稳定，此时抗拉强度和屈服强度分别为120 MPa和58 MPa，伸长率为34%，当退火温度升至420℃时，复合带材的综合力学性能较优。中间退火温度对芯材的显微组织演变具有重要影响，随着中间退火温度的增加，3003芯材的晶粒先后发生再结晶和晶粒长大，芯材的晶粒较大时复合带的抗下垂性能较好，故生产中为了获得良好的抗下垂性能可以适当提高芯材晶粒尺寸。成品前道次加工率为20%-30%，中间退火温度为370℃时，可以获得较理想的复合带材。

Abstract:

In order to obtain the optimal cold rolling composite process parameters, improve the properties of aluminum alloy composite strips, and provide a theoretical reference for industrial applications, 4004/3003/4004 laminated composite aluminum alloy was taken as the object.The effects of cold rolling composite process on the microstructure, sagging resistance and mechanical properties of 4004/3003/4004 aluminum alloy composite strips were analyzed by optical microscope, scanning electron microscope, muffle furnace and universal stretching machine and other equipment.The results show that more uniform cladding rate of composite strip can be obtained by cold rolling composite technology, and cold rolling one pass processing rate of 35% can make the core layer and cortex material achieve a strong combination.The sagging resistance of cold rolling composite strip first increases and then decreases with the increase of pre-processing rate of the finished products, while it shows an opposite trend with the change of intermediate annealing temperature.The sagging resistance of composite strip is the worst when the annealing temperature is 420℃.The mechanical properties of the cold rolling composite strip decrease sharply when the intermediate annealing temperature is 270-370℃.The mechanical properties of the composite strip begin to stabilize when the annealing temperature is 370℃.At this time, the tensile strength and yield strength are 120 MPa and 58 MPa, respectively, and the elongation is 34%.The comprehensive mechanical properties of the composite strip are better when the annealing temperature rises to 420℃.The intermediate annealing temperature has an important influence on the microstructure evolution of the core material.The grains of 3003 core material have recrystallized and grown successively with the increase of the intermediate annealing temperature.The sagging resistance of the composite strip is better when the grains of the core material are larger.Therefore, in order to obtain good sagging resistance in production, the grain size of the core material can be appropriately increased.The ideal composite strip can be obtained when the pre-processing rate of the finished product is 20%-30% and the intermediate annealing temperature is 370℃.