基于等温热压缩实验，分别获得了AA3003铝合金在变形温度为20～300℃，AA4343铝合金在变形温度为300～450℃，应变速率为0．01～1 s-1条件下的真实应力应变曲线，建立了AA4343铝合金的本构方程．采用DEFORM-2D软件，以AA3003为芯材，AA4343为包覆材料，分析了复合变形区长度、挤压速度和坯料温度对连续挤压包覆过程的影响．结果表明：随着复合变形区长度的减小，连续挤压包覆成形稳定时芯管的径向受力随之降低，合适的复合变形区长度为2．0 mm；随着挤压速度的增加，芯管出现了不同程度的变形，合适的挤压速度为0．1 mm/s；随着坯料温度的升高，芯管所受到的径向力随之减小，合适的温度范围为400～500℃．%The true stress-true strain curves of AA3003 and AA4343 aluminum alloy in the temperature range of 20~300 ℃ and 300~450℃, and in the strain rates range of 0.01~1 s-1 , were obtained by isothermal hot compression tests, and then the constitutive equation of AA4343 aluminum alloy was established. The influence of different processing parameters, such as length of clad forming zone, billet temperature and extrusion velocity, on the process of CONCLAD which select 3003 aluminum alloy as the core material and 4343 aluminum alloy as the cladding material was investigated with DEFORM-2D. The results show that the radial force of the core tube decreases as the length of clad forming zone increases during the steady state of CONCLAD process. With the increasing of extrusion velocity, the core tube exhibits deformation to different extent. With the increasing of billet temperature, the radial force of the core tube decreases. According to the analysis above, the optimal process parameters, such as length of clad forming zone 2. 0 mm, extrusion velocity 0.1 m/s and billet temperature 400~500 ℃, are obtained.
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