High Tensile Strength And High Conductivity In-Situ Deformation Composite Of Copper-Steel

With the fast development of electronic information technology,it asks for the properties of material increasing highly,and high strength and electrical conductivity copper-matrix composites(CMC)have been paid more and more attention,but the existing research results have been limited to a certain restrictions.The research on the basis of Cu-Fe composite material,wants to get higher strength CMC by instead of pure iron with lower-cost steelIt uses in situ deformation composite technology to get Cu-Fe composite material. The first step is to prepare Cu-Fe casting in a vacuum transformer furnace,secondly make surface working to the casting,and forge it to a slender rod in high temperature, then prepare solution treatment and aging treatment in different temperatures,the final process is to draw the rod to get the composite silk material.X-ray diffraction(XRD)is used to analyze the composite material structure at room temperature.Optical microscopy and scanning electron microscopy(SEM)are used to observe the change of the second phase microstructure with the shape variables when composite materials in the process of drawing.MTS is used to measure the change of tensile strength with shape variables when composite materials in the process of drawing.Portable DC double bridge is used to measure the change of resistor with shape variables when composite materials in the process of drawing.The main research results in this paper are as follows:(1)The second phase changes from tree crystal microstructure into parallel to the direction of drawing by forging and a series of drawing.The deformation is bigger,the fiber is more slim.Ultimately stateη=6.31,the average size of steel fiber is about 0.25μm and average fiber separation is about 1.50μm.(2)Iron atoms that solute in copper-matrix material have a large influence on the conductivity.After solid solution treatment to copper-steel composite material at 1000℃,20 min,the following aging process can promote iron atoms deposition from the copper-matrix.However,if aging temperature is too high,iron atoms would merge with copper-matrix again,resulting in the decrease the conductivity of the material.The best aging temperature for the aging 500℃(3)The increase of the composite material' s tensile strength is due to a large number of work-hardening and the second phase steel fiber reinforcement.The tensile strength and conductivity of copper- wt%11.5steel composite material that prepared by different processes are 862.22MPa/42.33%IACS;852.10MPa/52.39%IACS;823.76MPa/53.06% IACS;755.62MPa/57.86%IACS respectively.