【摘要】：本文系統(tǒng)研究了外加入法Cu-5wt%Cr復(fù)合材料的制備及其組織與性能。通過試驗(yàn)優(yōu)選出Cr顆粒的外加入方法和Cu-Cr復(fù)合材料鑄錠的制備工藝。采用X射線衍射儀、金相顯微鏡及掃描電子顯微鏡等觀察和分析了材料的微觀組織結(jié)構(gòu),特別是第二相Cr顆粒在冷拔變形中逐步形成纖維狀的組織演變規(guī)律;采用微機(jī)控制電子萬能試驗(yàn)機(jī)、直流雙臂電橋測試和分析了材料的力學(xué)性能和導(dǎo)電性能,重點(diǎn)研究了冷拔變形量及中間退火溫度對材料強(qiáng)度和導(dǎo)電率的影響規(guī)律。研究結(jié)果表明:Cu-Cr復(fù)合材料鑄錠的最佳制備方法為:采用真空感應(yīng)熔煉法,以球磨CuCr混合粉末壓制塊形式將Cr顆粒外加入至銅的熔體中,輔之以熔體的人工攪拌,使Cr顆粒均勻分布于銅熔體中,隨后再次抽真空脫除熔體中的氣體,制備Cu-Cr復(fù)合材料鑄錠。Cu-Cr材料在冷拔變形過程中,隨著變形量的增加,材料中的Cr顆粒第二相被拉長,逐漸形成纖維狀。由于原始組織的不均勻性,初期變形顆粒的取向差異和變形過程中第二相受到應(yīng)力大小的不一致,導(dǎo)致Cr顆粒的變形是不均勻的。退火使Cu-Cr復(fù)合材料中的Cr纖維發(fā)生彎曲、粗化、溶斷;退火溫度越高,纖維的粗化、溶斷現(xiàn)象越嚴(yán)重。Cu-Cr復(fù)合材料在冷拔變形過程中,隨著變形量的增加,材料的抗拉強(qiáng)度提高,導(dǎo)電率降低。經(jīng)過中間退火后,材料的抗拉強(qiáng)度降低,導(dǎo)電率提高。Cu-Cr復(fù)合材料在制備過程中,將材料的冷拔變形量與合理的中間退火工藝相組合,可以得到強(qiáng)度和導(dǎo)電率的良好配合,制備得到的Cu-5wt%Cr復(fù)合材料的抗拉強(qiáng)度達(dá)到640 MPa,導(dǎo)電率為61%IACS。
[Abstract]:The preparation, microstructure and properties of Cu-5wtCr composites by external addition method were studied systematically in this paper. The external addition method of Cr particles and the preparation process of Cu-Cr composite ingot were optimized by experiments. The microstructure of the material was observed and analyzed by means of X-ray diffractometer, metallographic microscope and scanning electron microscope, especially the evolution law of the second phase Cr particles gradually forming fibrous structure during cold drawing deformation. The mechanical properties and electrical conductivity of the materials were tested and analyzed by using a microcomputer controlled electronic universal testing machine. The effects of cold drawing deformation and intermediate annealing temperature on the strength and conductivity of the materials were studied. The results show that the optimum preparation method of Cu-Cr composite ingot is as follows: by vacuum induction melting, the Cr particles are added to the melt of copper in the form of ball milling CuCr mixed powder pressing block, supplemented by artificial stirring of the melt. The Cr particles are uniformly distributed in the copper melt, and then the gas in the melt is removed by vacuum again. During the cold drawing deformation of Cu-Cr composite ingot, the second phase of Cr particles in the material is elongated with the increase of the deformation amount. Gradually forming fibrous. Due to the inhomogeneity of the original structure, the orientation difference of the initial deformation particles and the inconsistency of the second phase stress during the deformation process lead to the inhomogeneous deformation of Cr particles. Annealing results in bending, coarsening and dissolution of Cr fibers in Cu-Cr composites. The higher annealing temperature, the thicker the fibers, the more serious the dissolution and fracture of Cu-Cr composites. During cold drawing deformation, the tensile strength of Cu-Cr composites increases with the increase of the amount of deformation. The conductivity is reduced. After intermediate annealing, the tensile strength of the material decreases, and the conductivity of the composite is increased. In the process of preparation, the cold drawing deformation of the material is combined with the reasonable intermediate annealing process, and the strength and conductivity of the composite can be well matched. The tensile strength of Cu-5wtCr composite is 640 MPA, and the conductivity is 61%.
【學(xué)位授予單位】：河北科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB33

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 姜訓(xùn)勇，李憶蓮，王童;高強(qiáng)度高導(dǎo)電銅合金[J];上海有色金屬;1995年05期

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本文編號(hào)：2127161