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摘要 本文以6063Al 合金作為基體，采用6063Al-K2ZrF6-Na2B4O7體系及熔體反應法，通過設計反應體系和改變具體工藝參數以制備不同質量分數的Al2O3p/6063Al復合材料。通過對Al2O3p/6063Al復合材料顯微組織觀察、X射線衍射及能譜分析可知，熔體反應可以自發(fā)進行，復合材料中有Al2O3顆粒生成，尺寸介于400~800nm之間，顆?；境拭琢罨蚪蛐?；對6063Al-K2ZrF6-Na2B4O7劑反應體系的SEM照片分析表明，反應在850°C時反應生成的Al2O3顆粒呈米粒狀或多邊狀，平均尺寸小于1μm，分布均勻，無明顯反應副產物及副產物長大現(xiàn)象。因此850°C為制備Al2O3p/6063Al復合材料最佳反應時間；從顆粒在熔體中的界面能角度出發(fā)，分析了可以導致顆粒在熔體內發(fā)生再分布的推移現(xiàn)象，表明減小顆粒粒徑、降低熔體粘度等方法可以改善顆粒在復合材料凝固過程中的分布狀況。

通過對塑性變形處理前后Al2O3p/ 6063Al復合材料的金相顯微組織研究結果表明：復合材料的大變形量的塑性變形由6063鋁合金基體晶粒內部的滑移來進行，隨著變形量的增大，基體晶粒和殘留相沿塑性加工方向被拉長，沿加工垂直方向被壓扁、破碎，最后趨于流線分布形成纖維組織；對塑性變形處理前后Al2O3p/ 6063Al復合材料的增強顆粒微觀形貌和分布的觀察發(fā)現(xiàn)，塑性變形前，Al2O3顆粒分布有一定的團聚現(xiàn)象，外觀具有棱角，基體內存在一定的夾雜相。塑性加工后，Al2O3顆粒團聚得到明顯改善，較大顆粒因受到剪切應力而破碎并呈現(xiàn)鈍角化的趨勢，夾雜相破碎并分散于基體中。

關鍵詞：顆粒增強鋁基復合材料，塑形加工，顯微組織，力學性能

In situ Al2O3 particles reinforced aluminum matrix composites 6063 microstructure and mechanical properties

Abstract  In this paper, 6063Al alloy as the matrix, using 6063Al-K2ZrF6-Na2B4O7 system and melt

reaction, the reaction system and change through the design of specific process parameters to produce different concentrations Al2O3p/6063Al composites. By Al2O3p/6063Al composite microstructure morphology, X-ray diffraction and EDS analysis, the melt reaction can occur spontaneously, the composite particles generated in Al2O3, size ranged between 400~800nm, rice-like particles substantially or nearly spherical; for 6063Al-K2ZrF6-Na2B4O7 agent of the reaction system SEM photograph analysis indicated that the reaction at 850°C when the reaction of Al2O3 particles were rice-like or multilateral having an average size of less than 1μm, evenly distributed, no obvious reaction byproducts and byproducts grown phenomenon. Therefore, 850°C for the preparation Al2O3p / 6063Al composite optimum reaction time; from the grain boundary can angle in the melt, analyzes the phenomenon can lead to redistribution of the passage of particles in the melt occurs, indicating that the particle size is reduced reduce melt viscosity and other methods to improve the distribution of particles in the composite solidification process.

    By studying the results of metallurgical microstructure before and after the plastic deformation process Al2O3p/6063Al composites show: a large amount of deformation of composite plastic deformation by a 6063 aluminum alloy matrix grains to slip, with the increase of deformation, bent along the matrix grain and residual plastic processingdirection is elongated along the machine vertically flattened, broken, and finally tends tostreamline the formation of fibrous tissue distribution; reinforcing particles before and after the plastic deformation process Al2O3p/6063Al composite microstructure and observe the distribution of discovery, before the plastic deformation, Al2O3 particle size distribution have a certain agglomeration, the appearance of having corners, there are some mixed phase matrix. After the plastic processing, Al2O3 particle agglomerationsignificantly improved due to the larger particles subjected to shear stress and broken the trend and showed an obtuse angle, mixed with crushed and dispersed in the matrix.

Key words:Particle reinforced aluminum matrix composites，Shaping process，Microstructure and mechanical properties

 

 

第一章 緒論

1.1 引言

復合材料是由兩種或兩種以上異質、異形、異性的材料復合形成的新型材料。在復合材料中通常有一相為連續(xù)相，稱為基體；有一種或幾種不連續(xù)相分布于基體中，不連續(xù)相的強度、硬度比連續(xù)相高，稱為增強體。增強體可以是纖維、顆粒狀填料等。按基體分類，復合材料可分為聚合物基復合材料(PMCs)、金屬基復合材料(MMcs)、陶瓷基復合材料(CMcs)。自上世紀80年代中期以來，顆粒增強金屬基復合材料得到了迅速的發(fā)展。其中，顆粒增強鋁基復合材料由于具有重量輕、比強度與比剛度高、剪切強度大、熱膨脹系數低、熱穩(wěn)定性高等優(yōu)點，并有良好的導熱性和導電性、卓越的抗磨性、對有機液體如燃料和溶劑的耐侵蝕性，以及可用常規(guī)工藝和設備進行成型與處理，被廣泛用于航空航天領域和汽車配件、體育用品等行業(yè)[1，2]。

但是，由于對顆粒增強金屬基復合材料的研究時間較短，加之影響其性能的因素錯綜復雜，所以現(xiàn)在對顆粒增強金屬基復合材料的制備、加工工藝還不完善，對其性能的了解也不全面。這些都將會影響和阻礙顆粒增強金屬基復合材料的工業(yè)化生產和推廣應用。

因此，為了更好的了解顆粒增強鋁基復合材料，本文采用6063A