共查询到19条相似文献,搜索用时 171 毫秒
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挤压铸造SiCp/2A50铝基复合材料的组织和力学性能研究 总被引:1,自引:0,他引:1
研究了在常规铸造工艺下使用挤压铸造方法制备SiC颗粒增强2A50的复合材料,分析了复合材料及增强相的微观组织,检测复合材料的室温力学性能,并探讨复合材料中SiC的强韧化机理以及SiC颗粒体积分数对力学性能的影响。研究表明,使用挤压铸造工艺制备的材料力学性能明显高于铝合金基体;SiCp/2A50复合材料力学性能的提高是位错强化、界面强化和时效强化等机制共同作用的结果;SiCp颗粒的体积分数应控制在20%左右,才能提高复合材料的力学性能。 相似文献
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超高强7090/SiCP复合材料的组织和性能 总被引:4,自引:0,他引:4
对喷射共沉积7090/SiCP复合材料坯经过挤压及不同热处理后棒材的微观组织和力学性能进行了研究,对其热处理工艺进行了确定.结果表明复合材料坯经挤压后组织细小均匀,SiC颗粒均匀分布;采用470℃×1 h+490℃×1 h的双级固溶处理及120℃×28 h时效后,挤压棒材的抗拉强度可达785 MPa,弹性模量超过100GPa;双级固溶+时效复合材料的力学性能明显优于单级固溶+时效态的力学性能;复合材料的断裂主要是由SiC颗粒断裂和界面脱粘引起. 相似文献
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采用液态搅拌法制备SiCp/ZL101复合材料,研究了SiC颗粒含量对材料抗拉伸强度和硬度的影响规律,同时还研究了固溶温度和时效温度对材料硬度的影响规律。结果表明,在本试验的SiC颗粒含量范围内,SiC颗粒含量越高,SiCp/ZL101复合材料的抗拉强度越高,伸长率越低;在排除缺陷等外来影响因素的条件下,SiCp/ZL101复合材料的硬度随着SiC含量的增加而提高。 相似文献
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真空热压烧结SiC_p/Al复合材料的界面元素扩散及增强断裂机理 总被引:1,自引:0,他引:1
采用真空热压粉末冶金烧结工艺制备了含SiC颗粒体积分数分别为 5 %、15 %和 2 5 %的SiC颗粒增强铝基复合材料 ,结合其力学性能、扫描电镜和界面微区能谱分析结果 ,分析了SiC/Al复合材料的真空烧结过程中的界面现象 ,以及材料增强和断裂机理。结果表明 ,真空烧结过程中出现了界面反应 ,改善了界面结合强度 ,断裂破坏主要在基体上进行。随着SiC粒子体积分数的增加 ,SiCp/Al复合材料的抗拉强度增加 ,弹性模量显著增加 ,延伸率降低 ,材料脆性增加。 相似文献
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采用粉末冶金法制备不同SiC粒径改性的SiC/C/Cu复合材料,研究SiC颗粒大小对材料组织结构和物理性能的影响;在载流摩擦磨损试验机上进行载流磨损试验,研究不同滑动速度下,SiC粒径对材料磨损率的影响。结果表明:在SiC/C/Cu复合材料中小颗粒SiC偏聚于C/Cu界面处,而大颗粒SiC均卡嵌在铜基体内,并且随着SiC颗粒的增大,复合材料硬度和密度稍有增加,孔隙率迅速降低,导电率增加;在较低滑动速度下,复合材料的磨损量随SiC粒径增大不断降低;在较高滑动速度下,随SiC粒径增大,复合材料的磨损率先降低后升高,25 μm SiC改性的复合材料具有最低的磨损率。 相似文献
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《润滑与密封》2016,(8)
采用粉末冶金法制备不同SiC粒径改性的SiC/C/Cu复合材料,研究SiC颗粒大小对材料组织结构和物理性能的影响;在载流摩擦磨损试验机上进行载流磨损试验,研究不同滑动速度下,SiC粒径对材料磨损率的影响。结果表明:在SiC/C/Cu复合材料中小颗粒SiC偏聚于C/Cu界面处,而大颗粒SiC均卡嵌在铜基体内,并且随着SiC颗粒的增大,复合材料硬度和密度稍有增加,孔隙率迅速降低,导电率增加;在较低滑动速度下,复合材料的磨损量随SiC粒径增大不断降低;在较高滑动速度下,随SiC粒径增大,复合材料的磨损率先降低后升高,25μmSiC改性的复合材料具有最低的磨损率。 相似文献
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In this study, the effect of wettability improvement of SiCp on the impact and sliding wear behavior of A356/20 wt% SiCp composites produced by a compocasting technique has been investigated. The result showed an increase of incorporation and uniform distribution of SiCp in the A356 matrix by elimination of SiCp segregation. Desired bonding between SiCp and the aluminum matrix due to improved wettability resulted in enhanced properties in terms of improved impact toughness and wear resistance. This improvement was also associated with partial refinement of coarse eutectic silicon due to increased incorporation and distribution of SiCp reinforcements. The highest enhancement was obtained when 1% Mg was added into the melt in addition to pretreated SiCp. The impact toughness value increased by 10 and 26% and the wear rate decreased by 5 and 30% when the SiC was treated and when Mg was added, respectively, compared to as-received SiCp. The impact fracture surfaces showed fewer decohered and well-bonded SiC particles in A356–(SiC-treated-Mg) composite. The highest wear resistance of A356/SiCp composites was achieved by A356–(SiC-treated-Mg) composite for applied loads of 10 and 20 N compared to other fabricated composites. The worn surface revealed mild abrasion and adhesion wear mechanisms. 相似文献
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采用喷射沉积法制备15%(体积分数)4.5 m SiCp/Al-20Si复合材料及其基体合金,研究该组材料的微观组织、力学性能、高周疲劳性能以及疲劳断口形貌。结果表明:SiC颗粒的加入有利于提高材料的力学性能;复合材料及其基体的高调疲劳寿命随应力幅值的减小而增加,在相同应力幅值下,复合材料的疲劳寿命远远高于基体合金。疲劳裂纹从大颗粒的初晶Si的断裂以及Si相脱离处形核,并开始扩展。对于复合材料而言,SiC颗粒尺寸较小,不容易发生断裂,在形核过程中,当裂纹遇到SiC颗粒时,裂纹或者避开增强体,或者受阻于SiC颗粒,只能在基体合金中扩展,从而扩大了疲劳形核区的面积,提高了材料的疲劳寿命。Si颗粒的脱离、Si相的断裂以及SiC颗粒与基体界面的脱粘是复合材料疲劳断裂失效的主要机制。 相似文献
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Parviz Asadi Ghader Faraji Mohammad K. Besharati 《The International Journal of Advanced Manufacturing Technology》2010,51(1-4):247-260
Friction stir processing (FSP) was used to fabricate SiC/AZ91 composite layer. Effect of process parameters such as rotational and traverse speeds, tool penetration depth and tilt angle on the formation of defects such as cracks, tunnelling cavity and also on sticking of matrix material to the tool was investigated. Also, effect of these parameters was studied on the mechanical properties and microstructures of specimens. Microstructure studies were carried out by optical and SEM. Results showed that FSP is an effective process to fabricate SiC/AZ91 composite layer with uniform distribution of SiC particles, good interfacial integrity and significant grain refinement. Increasing the rotational speed leads to a decrease in the grain size and an increase in the traverse speed leads to a decrease in the grain size. There are upper and lower limitations for these speeds which were determined. PD is a more effective parameter to produce sound surface layer. PD value was affected by traverse and rotational speeds and the tilt angle values. This study shows that by using 5 μm SiC particles, the stir zone grain size reduces from 150 to 7.17 μm and stir zone hardness increases from 63 to 96 Hv. 相似文献
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It can be known from a large number of research results that improving the dispersibility of CNTs can effectively opti-mize the mechanical properties of the corresponding metal matrix composites.However,the crucial issue of increas-ing the bonding of CNTs and the matrix is still unsolved.In this paper,a novel method was developed to increase interfacial bonding strength by coating titanium oxide(TiO2)on the surface of CNTs.The rare earth Pr and TiO2@CNTs-reinforced AZ91 matrix composites were successfully fabricated by powder metallurgy.Hot press sintering and hot extrusion of the milled powder was performed.After hot extrusion,the influence of TiO2@CNTs on the microstruc-ture and mechanical properties of the composites were investigated.The results showed that the coating process can improve the distribution of CNTs in Mg alloy.The CNTs refined the grains of the matrix,and the CNTs were presented throughout the extrusion direction.When the TiO2@CNTs content was 1.0 wt.%,the yield strength(YS),ultimate ten-sile strength(UTS),and elongation of the alloy attained maximum values.The values were improved by 23.5%,82.1%,and 40.0%,respectively,when compared with the AZ91 alloy.Good interfacial bonding was achieved,which resulted in an effective tensile loading transfer at the interface.CNTs carried the tensile stress and were observed on the tensile fracture. 相似文献
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采用热压烧结法制备了三种不同成分的SiC颗粒增强镁-锌-锆基复合材料,使用LMR-1型低频力学弛豫谱测试系统研究了铸态镁-锌-锆合金及热压烧结SiCp/镁-锌-锆基复合材料的阻尼性能随频率和温度的变化关系.结果表明:SiC颗粒的加入使复合材料的阻尼性能比基体合金有显著提高;另外随着合金中锌含量的增加,复合材料的内耗值不断下降;在频率为3×10-3~7Hz范围内,基体合金及复合材料的内耗值均随着频率的增加先快速减小随后又逐渐增大;在本试验条件下SiCp/Mg-0.93%Zn-0.70%Zr基复合材料的内耗值最大,该复合材料在50~100℃的温度范围内出现弛豫内耗峰. 相似文献