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铜/钛双金属复合管兼具铜的导热性和钛的耐海水腐蚀性,是海军舰船、滨海电站的各类海水管路和蒸汽管路系统理想材料.本文采用热旋锻方法成功制备了界面结合性能良好的铜/钛双金属管,重点研究了变形温度、道次变形量等重要工艺参数对管材结合性能的影响,明确了旋锻过程中双金属的结合机制.研究结果表明,在旋锻温度600～ 900℃,道次变形量45％～70％的制备工艺条件下可成功制备界面冶金结合、结合性能优异的铜/钛双金属复合管,且旋锻温度越低,所需道次变形量越大.在旋锻温度800 ℃,变形量54.6％条件下制备的铜/钛复合管的平均界面结合强度为13.3 N·mm-1,最大剥离强度可达26.5 N·mm-1,整管抗拉强度为303.1 MPa,断后伸长率为23.5％,复合界面在极大的压扁弯曲变形下仍不会分层,变形协调性优异.分析认为热旋锻方法制备双金属复合管的界面结合机制为:两金属表面碰撞接触的瞬间氧化膜因表层金属的流动而破裂,新鲜金属基体互相咬合,实现物理结合,同时界面两侧的原子在高温热激活作用下产生相互扩散,达到冶金结合.

Combining excellent thermal conductivity of copper with good corrosion resistance to seawater of titanium,copper/titanium bimetal composite pipe was an ideal material of sea water pipelines and steam pipelines system used in naval ships,coastal power station.In this paper,Cu/Ti bimetallic pipes with good interfacial bonding properties were successfully fabricated by the heating rotary swaging.The effects of the key parameters,such as deformation temperature and pass deformation,on the bonding properties of the pipes were investigated,and the binding mechanism of bimetal during swaging was clarified.The results showed that the Cu/Ti bimetallic composite pipes with a metallurgical bonding state and excellent bonding properties could be successfully prepared by heating rotary swaging at the temperature of 600 ～900 ℃ and the single pass deformation of 45％～70％,and the lower the temperature,the greater the single deformation required.The Cu/Ti composite pipes prepared at the temperature of 800 ℃ and the deformation of 54.6％ had some good properties with the average interfacial bonding strength of 13.3 N·mm 1,the maximum peel strength of 26.5 N·mm-1,the tensile strength of the whole tube of 303.1 MPa,and the elongation after fracture of 23.5％.The composite interface would not delaminate under the greatest flattening deformation,and showed an excellent compatibility of deformation.The analysis on the interfacial bonding mechanism of bimetallic composite pipes prepared by heating rotary swaging suggested that two metals instantaneous collided with each other in their interface,then the oxide film between them cracked because of the flow of metal during the contact,and fresh metal matrix interlocked to achieve a physical bonding.At the same time,the atoms on both sides of the interface were interdiffused under the effect of heat activation of high temperature to reach a metallurgical bonding.