【作者】 徐迎华；

【导师】 齐育红； 黑祖昆；

【作者基本信息】 大连海事大学 ， 载运工具运用工程， 2003， 硕士

【摘要】 准晶材料的脆性限制了其作为结构材料的应用，所以科学家们将准晶颗粒与软基体材料复合，从而达到强化基体的目的。本文主要就热处理对Al₆₅Cu₂₀Cr₁₅准晶颗粒增强Al基复合材料的力学性能和微观组织的影响进行了较系统的研究。 本文利用了SEM、XRD、DSC对不同热处理条件的Al₆₅Cu₂₀Cr₁₅／Al试样进行了分析，并测试了其宏观硬度、微观硬度、拉伸性能、压缩性能和磨损性能。得出以下结论： 1．热压状态基体为纯铝，在其它几种热处理状态下试样的基体上都有CuAl₂相析出，但CuAl₂的析出量并不相同，退火状态下CuAl₂的析出量最多，淬火状态下最少，随时效时间的延长，CuAl₂的析出量逐渐增多。在这几种热处理状态下准晶发生了相变。 2．本复合材料的材料的宏观硬度随时效时间的增加而升高。时效4小时试样的硬度最高（75.8MPa），比热压试样的硬度（19.0MPa）提高了56.8MPa。基体的显微硬度随时效时间的增加而升高，与其宏观硬度的变化规律基本类似。在这几种热处理状态下本复合材料的宏观硬度变化规律与普通Al-Cu合金类似。 3．本复合材料的断裂强度（σ_b）、屈服强度(σ_0.2)、延伸率（δ）及弹性模量（E）随时效时间的延长而升高。热压态试样的塑性最好（相对压缩率达到37％）。本复合材料断裂表现为脆性断裂。 4．时效时间越长本复合材料的耐磨性越好；退火试样的抗磨损能力最高。在干摩擦条件下本复合材料的磨损机制是以磨粒磨损为主，伴有粘着磨损和氧化磨损。更多还原

【Abstract】 The brittleness of quasicrystal restrains its application as structural material, In order to strengthen the base, the quasicrystalline particles were composed with soft matrix. Wear properties of this sample with different heat treatment were analyzed by wear test, mechanical properties were analyzed by mechanical test such as micro hardness test, macro hardness test, tensile test, compression test, the morphological and structural were obtained by SEM, XRD and DSC. The main conclusions were reached as follows:1. In the state of hot pressure, the matrix was pure Al. Lots of precipitation of CuAla was obtained from the base after aging, precipitation of CuAb was a little after quenched, and precipitation of CuAb grew more with aging time going. The phase of the quasicrystalline particles has transformed.2. The macro hardness of the composite became higher with time going on. The hardness became the highest (78.86MPa) with aging of 4 hours, it was 56.8MPa higher than that of composite in the state of hot press. The micro hardness of matrix got higher with the time going, which was similar with the law of macro hardness.3. The fracture strength( o b), the yield strength( o s), the extension ratio( 6 )and the Young’s modulus( E) rose with aging time going on. The plastic property was the best in the state of hot press. The fracture mechanism of this composite was brittle fracture.4. The longer the aging time was, the higher wear resistance this composite had. Wear resistance of samples was the best in the state of annealing. The wear mechanism of this composite was mainly abrasive particles wear, accompanying adhesive wear and oxidation wear.更多还原