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摘要：本文采用熔體原位反應(yīng)法制備原位顆粒增強ZrB2/2024鋁基復(fù)合材料，工藝簡單，制備成本低，易推廣，但是由于鑄造缺陷的存在以及鑄造條件的限制，其結(jié)構(gòu)性能不高，增強相尺寸、形貌、在基體合金中分布均勻性不理想。因此對復(fù)合材料進行了攪拌摩擦塑性加工，改善復(fù)合材料的微觀結(jié)構(gòu)，提高材料內(nèi)部結(jié)構(gòu)的致密性，減少鑄造缺陷，從而提高材料的綜合性能。通過金相顯微鏡鏡（OM）、X射線衍射儀(XRD)、掃描電子顯微鏡鏡（SEM）等分析設(shè)備， 研究攪拌摩擦加工對顆粒增強ZrB2/2024鋁基復(fù)合材料微觀結(jié)構(gòu)及性能的影響。

對鑄態(tài)復(fù)合材料的微觀形貌進行研究，發(fā)現(xiàn)制備的復(fù)合材料中ZrB2顆粒較大。攪拌摩擦后的ZrB2/2024鋁基復(fù)合材料的微觀組織表明，攪拌摩擦后復(fù)合材料獲得了較細晶粒（3~9μm），增強顆粒彌散分布，團聚現(xiàn)象消除。硬度、摩擦磨損性能都得到了提升。 

攪拌摩擦加工后，基體晶粒破碎，變得細小，晶粒形狀也發(fā)生了改變；材料的抗拉強度變大（由160MPa到220MPa）、延伸率變大（由8.05%到17.4%），韌性斷裂明顯；硬度變大（由38.00HBW 到76.94HBW）。摩擦系數(shù)隨載荷的增加而不斷升高，而且變化逐步趨于穩(wěn)定，說明攪拌摩擦后的復(fù)合材料具有較好的摩擦穩(wěn)定性。

關(guān)鍵詞：塑性變形；攪拌摩擦加工；復(fù)合材料；力學(xué)性能；摩擦磨損；

 

Effects of plastic deformation on in situ ZrB2 / 2024Al Mechanical Properties

Abstract：This article was prepared using a melt-situ reaction in situ particle reinforced ZrB2 / 2024 aluminum matrix composites, simple process, low production cost, easy to promote, but due to the conditions and restrictions casting casting defects, and its structure is not high performance, enhanced - size, shape, uniformity is not satisfactory in the matrix alloy. Therefore, composite materials were plastic friction stir processing, improve the microstructure of composite materials to improve the internal structure of dense material, reducing casting defects, thereby improving the overall performance of the material. By optical microscope lens (OM), X-ray diffraction (XRD), scanning electron microscope microscope (SEM) and other analytical equipment, research FSP particle Reinforced ZrB2 / 2024 aluminum matrix composite microstructure and properties.

  Cast microstructure of the composite material, and found that a composite material in ZrB2 larger particles. Microstructure ZrB2/2024 aluminum matrix composites friction stir after the show, after friction stir composites obtained finer grains (3~9μm), reinforcing particles dispersed, agglomeration eliminated. hardness, friction and wear properties have been improved.

  After stirring friction processing, matrix grain crushing, becoming tiny, grain shape has changed; the tensile strength of the material becomes larger (by a 160MPa to 220MPa), elongation increases (from 8.05% to 17.4%), plastic fracture is obvious; hardness increases (by the 38.00HBW to 76.94HBW).With the increase of the friction coefficient and the load rising, but changes gradually stabilized, after friction stir described composite having good friction stability.

Keywords：Plastic deformation; friction stir processing; composite; mechanical properties; friction and wear;