冷加工和热处理对添加硼铈的弥散强化铜性能的影响

Effect of cold working and heat treatment on properties of dispersion strengthened copper with addition of B and Ce

添加稀土铈和硼,采用溶胶凝胶和粉末烧结制备了新型氧化铝弥散强化铜。通过维氏硬度仪、扫描电镜和光学显微镜研究了冷加工率和热处理对其性能的影响。结果表明:在Cu+Al_2O_3基体中加入修饰剂硼和铈后,合金的晶格发生畸变,晶粒尺寸变小,是弥散强化铜硬度提高的主要原因。加入稀土元素铈对提高弥散强化铜的硬度比添加硼更显著。在箱式加热炉中研究了400、600、700℃加热时对其致密度的影响,发现在600℃时添加微量铈和硼,是组织细化和提高致密度的最佳温度,而加入稀土元素铈则效果更佳。

By the addition of rare earth Ce and B, a new type of aluminum oxide dispersion strengthened copper was prepared by sol-gel and powder sintering method. The effect of cold working rate and heat treatment temperature on properties of the alloy was studied by means of Vickers hardness test, scanning electron microscopy and optical microscope. The results show that with the addition of boron and cerium in the Cu ＋ Al2O3 matrix, the lattice distortion of the alloy and the decrease of the grain size are the main reasons for the improvement of the hardness of the dispersion strengthened copper. Adding Ce is more effective than adding B on improving the hardness of the dispersion strengthened copper. Effect of annealing at different temperatures （400℃ , 600℃ and 700 ℃） on the density of the alloy was studied. It is found that the best temperature for the refinement of the microstructure and the increasement of the density of the alloy with addition of cerium and boron is 600℃. Moreover, adding rare earth Ce has better effects than adding B. Keywords：dispersion strengthened copper; annealing temperature; cold working rate; rare earth Ce