| Contact cable is an important part of the electrical railway system. Copper alloy contact cable is the most common type of cables used as so far. Chronically there exits a contradiction between the requirement of high strength and that of high conductivity during the study of copper contact cable and even this contradiction runs through the research of all conductive materials. Manufacturing the contact cable by material composite technology is a newly developed method in recent years. Due to its anisotropism and excellent ability of interfacial combination, in-situ composite shows a wonderful potential to giving the attention to the strength and the conductivity of conductive materials at one time. The key direction in the current research of in-situ composite contact cable is how to continuously steadily produce it and so to realize the industrialization of it. Just on the consideration of all above, in this dissertation the continuous casting procedure of in-situ composite Cu-Cr alloy and its technological characteristics as well as the structure and properties of contact cable are deeply researched, the interactions among the technical parameters of directional solidification continuous casting (DSCC) process are analyzed, and also the real-time-control characteristics and methods of parameters are discussed. The purpose of all work is to make the foundation of industrialization of in-situ composite contact cable.First, the process of contact cable castings of in-situ composite Cu-Cr alloy by means of DSCC, as well as its effects to contact cable's structure and properties, is lucubrated in this paper. The in-situcomposite Cu-Cr alloy by DSCC has a feature on macrostructure that columnar grains directionally ranks on the axial direction of the castings, and its microstructure has a general pattern as following: primary a (Cu) crystals are cellular or columnar and strip particles (Cr) and eutectic [ + ] alternately distributes between any two primary (Cu) grains. This forms regularly two-phase-alternation in-situ composite materials among which the (Cu) plays the rule of electricity-conduction while the (Cr) that of strengthening. This type of microstructure results in that the strength of conductive materials is improved well and the conductivity along direction of electricity transmission slightly decreases due to anisotropism character of the material with directional structure.Second, standard contact cable samples are made from in-situ composite Cu-Cr castings and effects of the subsequent process technology of castings on its structure and properties are investigated. Cold-drawn in-situ composite contact cable samples still keep a structure conformation like as-cast structure so that their tensile strength is improved greatly and their electricity conductivity decreases slight but all in all their synthetic properties are obviously higher than those of castings. As-cast in-situ composite Cu-Cr alloy's tensile strength is about 300~350MPa, elongation rate between 30%~40%, and relative conductivity around 87%~95%, so as to 9.6x106MPa2 % of synthetic property; Cold-drawn contact cable samples' tensile strength is up to 400~460MPa and relative conductivity down to 80%~85% so that the synthetic property can be up to 18.3xl06MPa2 % maximally. Also it is found with heat-treatment experiments that the in-situ composite contact cable has of excellent thermal stability as following: its synthetic property varies little after 3 h soaking at 500 C.In addition, the forming conditions of the S/L interface locationand the influencing factors on them, during the continuous casting of in-situ composite Cu-Cr contact cable, which is the key for continuously directional solidification structure of materials, are systematically studied. Although DSCC process has 6 controllable technical parameters shown by numerical simulation, the S/L interface location and S/L interface shape-factor are greatly relevant to 3 parameters of all, such as the cooling distance Lc, the mold exit temperature Tm, and the pulling...
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