(
(昆明理工大學(xué) 材料科學(xué)與工程學(xué)院，昆明 650093)
摘 要: 采用固−氣共晶定向凝固的方法制備規(guī)則多孔銅，研究其室溫拉伸性能的各向異性和氣孔率對拉伸力學(xué)性能的影響，建立表征抗拉強度與氣孔率和拉伸方向相關(guān)的數(shù)學(xué)模型。結(jié)果表明：規(guī)則多孔銅的拉伸性能主要取決于材料的氣孔率和拉伸方向；隨著氣孔率的增大，規(guī)則多孔銅的拉伸性能明顯下降；規(guī)則多孔銅拉伸性能呈各向異性特征，0°方向性能最好，45°方向的次之，90°方向的最差；各拉伸方向的實驗數(shù)據(jù)與模型數(shù)據(jù)吻合良好。斷口分析表明：規(guī)則多孔銅呈韌性斷裂，拉伸斷裂從孔壁處開始，最終因頸縮導(dǎo)致完全斷裂。
關(guān)鍵字: 規(guī)則多孔銅；各向異性；力學(xué)性能；氣孔率；應(yīng)力集中
（School of Materials Science and Engineering,
Kunming University of Science and Technology, Kunming 650093, China）
Abstract:The ordered porous copper with cylindrical pores aligned in one direction was fabricated by the solid-gas eutectic solidification process. The anisotropy of tensile properties and the porosity of ordered porous copper at room temperature were investigated. In order to discuss the effects of porosity and tensile direction on ultimate tensile strength, the stress concentration models were established. The results show that the tensile properties of ordered porous copper depend on the porosity and tensile direction. As the porosity increases, the tensile properties decrease dramatically. The anisotropy of porous copper shows that the tensile properties of ordered porous copper with 0°, 45° and 90° tensile directions are the best, better and the worst, respectively. The experimental data are well consistent with the data from the model. Through fractographic analysis, it is indicated that the ductile fracture begins at the inside walls of pores, and the eventual rupture is due to necking during the tensile process.
Key words: ordered porous copper; anisotropy; mechanical properties; porosity; stress concentration
