INFLUENCE OF INDUCTION HEATING CONTINUOUS ANNEALING ON RECRYSTALLIZATION AND INTER- FACIAL INTERMETALLIC COMPOUND OF COPPER-CLAD ALUMINUM WIRE
JIANG Yanbin1,2, LIU Xinhua1,2, WANG Chunyang1, MO Yongda1, XIE Jianxin1,2
1 Key Laboratory for Advanced Materials Processing of Ministry of Education, Institute of Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 2 Beijing Laboratory of Metallic Materials and Processing for Modern Transportation, University of Science and Technology Beijing, Beijing 100083
Cite this article:
JIANG Yanbin, LIU Xinhua, WANG Chunyang, MO Yongda, XIE Jianxin. INFLUENCE OF INDUCTION HEATING CONTINUOUS ANNEALING ON RECRYSTALLIZATION AND INTER- FACIAL INTERMETALLIC COMPOUND OF COPPER-CLAD ALUMINUM WIRE. Acta Metall Sin, 2014, 50(4): 479-488.
Influences of induction heating continuous annealing (IHCA) on the microstructure of both copper sheath and aluminum core, and intermetallic compound at the Cu/Al interface of cold-drawn copper-clad aluminum wire were investigated, compared with the traditional isothermal annealing in furnace (TIA). The results showed that recovery of both the copper sheath and aluminum core happened when the temperature of IHCA was 250 ℃. Recrystallization began to occur in the copper sheath at 300 ℃ and in the aluminum core at 330 ℃, respectively. Complete recrystallization of both the copper sheath and aluminum core took place at 430 ℃, whose average grain size were 6.0 and 7.3 μm, respectively. An intermetallic compound CuAl2 discontinuously formed at the interface at 360 ℃, and continuous CuAl2 layer formed at 390 ℃. Both CuAl2 layer and Cu9Al4 layer formed at the interface at 430 ℃, with average thickness of 0.52 and 0.48 μm, respectively. With further raising the temperature, the grains of both copper sheath and aluminum core grew, and the thickness of the intermetallic compound layer increased slightly. The appropriate IHCA temperature of the cold-drawn copper-clad aluminum wire was 430 ℃. Compared with TIA, IHCA was able to not only refine recrystallized grain of both copper sheath and aluminum core remarkably, but also reduce the thickness of the interfacial intermetallic compound layer in the copper-clad aluminum wire.
Fund: Supported by National Natural Science Foundation of China (No.51104016), National High Technology Research and Development Program of China (No.2013AA030706) and Fundamental Research Funds for the Central Universities of China (Nos.FRF-TP-12-147A, FRF-MP-10-004B and FRF-TP-12-146A)
