Embedded aluminum-steel composite sheets used in heat exchanger were produced by cold roll bonding(CRB). The influences of annealing temperature and annealing time on the microstructure and the bonding strength of the...Embedded aluminum-steel composite sheets used in heat exchanger were produced by cold roll bonding(CRB). The influences of annealing temperature and annealing time on the microstructure and the bonding strength of the composite sheet were investigated. The recrystallization of the steel layer began at 525℃ and finished at 600℃. With the increase of the annealing temperature, the peel strength of the composite sheet whose original steel sheet surface was treated by scratch brush initially increased and then decreased, which was resulted from the competition of the mechanical locking and metallurgical bonding. After annealing, the cracks which formed between the broken work-hardened steel surface layer and its matrix during cold roll bonding remained. The composite sheet produced by CRB with the steel surface treatment of flap disc had less interfacial defects, higher bonding quality, higher diffusion rate of Al and Fe atoms at the interface and larger metallurgical bonding extent than the composite sheet produced by CRB with the steel surface treatment of scratch brush under the same conditions of annealing,which was helpful to shorten annealing time, reduce energy consumption and improve production efficiency.展开更多
基于热锻条件,使用销-盘摩擦设备对6061热锻铝合金和H13钢基自润滑模具材料进行了高温对磨实验,通过电子探针和能谱仪分析了不同工况下工件和模具的磨损机理。结果表明,随着载荷的增加,工件和模具之间的摩擦因数与磨损率先降低后升高;...基于热锻条件,使用销-盘摩擦设备对6061热锻铝合金和H13钢基自润滑模具材料进行了高温对磨实验,通过电子探针和能谱仪分析了不同工况下工件和模具的磨损机理。结果表明,随着载荷的增加,工件和模具之间的摩擦因数与磨损率先降低后升高;随着转速的增加,工件和模具之间的摩擦因数增大,磨损率呈倍数增加;当载荷为12 N、转速为100 r·min^(-1)时,工件和模具之间的摩擦因数最小,其值为0.416,磨损率仅为24.591 mm 3·N^(-1)·m^(-1);随着转速和载荷的增加,工件和模具之间的粘着磨损加重并且逐渐出现磨粒磨损和氧化磨损。展开更多
基金supported by the National High Technology Research and Development Program of China (2013AA031301)the National Natural Science Foundation of China (51104016)the Natural Science Foundation of Jiangsu Province (BK20161151)
文摘Embedded aluminum-steel composite sheets used in heat exchanger were produced by cold roll bonding(CRB). The influences of annealing temperature and annealing time on the microstructure and the bonding strength of the composite sheet were investigated. The recrystallization of the steel layer began at 525℃ and finished at 600℃. With the increase of the annealing temperature, the peel strength of the composite sheet whose original steel sheet surface was treated by scratch brush initially increased and then decreased, which was resulted from the competition of the mechanical locking and metallurgical bonding. After annealing, the cracks which formed between the broken work-hardened steel surface layer and its matrix during cold roll bonding remained. The composite sheet produced by CRB with the steel surface treatment of flap disc had less interfacial defects, higher bonding quality, higher diffusion rate of Al and Fe atoms at the interface and larger metallurgical bonding extent than the composite sheet produced by CRB with the steel surface treatment of scratch brush under the same conditions of annealing,which was helpful to shorten annealing time, reduce energy consumption and improve production efficiency.
文摘基于热锻条件,使用销-盘摩擦设备对6061热锻铝合金和H13钢基自润滑模具材料进行了高温对磨实验,通过电子探针和能谱仪分析了不同工况下工件和模具的磨损机理。结果表明,随着载荷的增加,工件和模具之间的摩擦因数与磨损率先降低后升高;随着转速的增加,工件和模具之间的摩擦因数增大,磨损率呈倍数增加;当载荷为12 N、转速为100 r·min^(-1)时,工件和模具之间的摩擦因数最小,其值为0.416,磨损率仅为24.591 mm 3·N^(-1)·m^(-1);随着转速和载荷的增加,工件和模具之间的粘着磨损加重并且逐渐出现磨粒磨损和氧化磨损。