铜包铝和长碳纤维层状复合材料压力充芯连铸精密成形技术基础

The frequency of information transmission is very high. According to the principle of conductor skin effect, the conductors of copper cladding aluminum composite materials have the same properties as pure copper conductors because high frequent electromagnetic wave only transmits through the surface of the conductors. In order to increase the strength and decrease the density of the conductors, in this subject, a new method for producing composite materials of copper cladding aluminum and long carbon fiber is introduced, which uses the technology of pressure and core filling continuous cast to prepare copper cladding aluminum and long carbon fiber composite compacts, then then copper cladding aluminum and long carbon fiber composite materials with the right diameters can be produced after pressure drawing process..Advantages of using this technology can be expressed as： First, the productivity is very high. The copper tube continuous casting and the aluminum and long carbon fiber core filling proceed at the same time, which can be used to cast small scale composite compacts with high strength and low density . Second, joint state of copper aluminum long carbon fiber interface are very excellent. After disengage from the inside crystallizer, the inner wall of copper tube directly contacts with liquid aluminum of core filling, so that there is no oxide or greasy dirt on interface and the metallurgical bonding can be obtained easily. Third, it is easy to control the interface microstructure of copper aluminum and long carbon fiber by means of the aluminum under high pressure and long carbon fiber be heating in the path..This subject mainly studies the rule of metal fluxion, mechanism of heat diffusion and mass transfer as well as the quality of interface and its influencing factor. In addition, the proper matches and control of processing parameters, and technological prototype are also studied. This subject can lay a foundation for a wide application in industry.

信息传输的频率很高，根据"趋肤效应"原理，高频信号仅集中在导体的表面传输，所以铜包铝复合导体具有与纯铜导体完全相同的高频传输性能。为了提高导体的抗拉强度和减少其密度，本项目提出一种制备铜包铝和长碳纤维复合材料的新思路：采用"连铸"制备铜管，同时向铜管中"充芯"铝液和长碳纤维，加压使铝在"压力"下凝固，使铜管被"压出"，形成铜包铝和长碳纤维复合材料。其特点：①生产率高，在连铸铜管的同时，充填芯部铝液和长碳纤维，直接进行复合，适合于制备高强度低密度复合材料；②铜、铝与碳纤维界面结合状态好，铜管的内壁在成形脱离内结晶器后，直接与充芯的铝液接触，界面无氧化物和油污；③碳纤维在导向管中被加热粗化，铝在压力下凝固，易实现铜、铝与碳纤维复合界面组织的控制。本项目重点研究铜包铝和长碳纤维压力充芯连铸成形过程中传热传质规律，界面质量及其影响因素，工艺参数的合理匹配与控制，确定技术原型，为工业应用奠定基础。

信息传输的频率很高，高频信号仅集中在导体的表面传输，所以铜包铝复合导体具有与纯铜导体完全相同的高频传输性能。为了提高导体的抗拉强度和减少其密度，本项目提出一种制备“铜（银）包铝和长碳纤维压力充芯连铸”工艺（Copper or Silver Cladding Aluminum and Carbon Fiber Pressure Core Filling Continuous Cast，简称“Cu(Ag)AlC-3C”工艺）：采用“连铸”制备铜管，同时向铜管中“充芯”铝液和长碳纤维，加压使铝在“压力”下凝固，使铜管被“压出”，形成铜包铝和长碳纤维复合材料。. 1、研究了“Cu(Ag)AlC-3C”工艺短流程制备复合成形过程中温度场和浓度场的变化规律，寻找到试验设备关键尺寸、工艺参数与获得良好复合导体的温度场、浓度场之间的定量关系，为试验设备设计和进行有效工艺控制提供定量参考依据。. 2、设计和制造了“CuAlC-3C”工艺试验设备，可制备外径φ3-30mm、铜体积比例10-15%、长碳纤维体积比例1.2-21.0%，其余是铝。抗拉强度达到1-10倍于纯铜的抗拉强度，其密度比铜包铝轻0.3-5.1%。. 3、重点研究了铜包铝和长碳纤维复合导体压力充芯连铸的短流程制备成形的相关基础问题，获得：①外层金属铜在“压力连铸”的运动状态下与“充芯”金属铝和长碳纤维之间的传热与传质的规律、界面反应行为及其控制参数；②外层金属控温结晶器、复合界面加压装置和充芯管的关键尺寸、材料、温度、加压压力、充芯连铸拉拔退让速度、外层金属的浇注温度、芯部金属铝的充芯温度、二次冷却装置的位置及冷却强度等对复合界面质量的影响规律；③复合质量良好的铜包铝和长碳纤维复合导体的“压力充芯连铸”工艺参数的最佳匹配关系。. 确定了技术原型，证明本项目提出一种制备铜包铝和长碳纤维复合材料的思路是可行的，其特点：①在连铸铜管的同时，充填芯部铝液和长碳纤维，直接进行复合，适合于制备高强度低密度复合材料；②铜、铝与碳纤维界面结合状态好，铜管的内壁在成形脱离内结晶器后，直接与充芯的铝液接触，界面无氧化物和油污；③碳纤维在导向管中被加热粗化，铝在压力下凝固，易实现铜、铝与碳纤维复合界面组织的控制。为工业应用奠定了基础。