共查询到19条相似文献,搜索用时 468 毫秒
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Y对镁合金AZ91力学性能的影响 总被引:1,自引:1,他引:1
为了找出稀土元素Y对镁合金AZ91力学性能的影响作用,从而为改善镁合金AZ91的力学性能和拓宽镁合金AZ91的应用领域提供依据,采用室温和高温拉伸试验,辅以断口分析和组织观察,对室温和150℃下不同Y含量的镁合金AZ91的抗拉强度和延伸率等力学性能进行了研究,得出了镁合金AZ91的力学性能随Y含量的变化关系.结果表明,随着稀土元素Y的增加,室温下的抗拉强度逐渐增加,延伸率略有增加;150℃下的抗拉强度逐渐增加,延伸率逐渐降低.加入适量的Y可改善镁合金AZ91的力学性能,使其满足高温下的应用要求. 相似文献
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采用压缩圆柱形镁合金铸锭的试验方法,研究了不同变形温度和不同应变速率对AM60B铸态镁合金塑性流动应力的影响规律。采用电子显微镜观察了压缩试样微观组织,结果显示,镁合金在高温下塑性变形以基滑移为主,并出现位错攀移,在临近晶界处有明显的交滑移产生。采用数理统计的方法建立了变形温度为573-673K、应变速率为0.01~0.1s^-1条件下的AM60B铸态镁合金塑性变形本构模型,试验表明所建立的本构模型能充分反映AM60B铸态镁合金的塑性变形规律。 相似文献
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AZ31变形镁合金等温变形力学特性的研究 总被引:11,自引:0,他引:11
针对AZ31镁合金,采用Gleeble1500热模拟试验机对其在不同温度和变形速率下的流变应力进行了实验研究,结果表明镁合金在进行高温压缩的情况下,变形温度和应变速率对流变应力有显著的影响,流变应力随应变速率的升高和变形温度的降低而升高。在此基础上,建立了流变应力的数学模型,其结果为镁合金的塑性成形工艺的制订提供理论依据。 相似文献
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于俊才 《机械工人(热加工)》2011,(1):43-44
镁合金作为最有潜质的轻质结构材料,具有高比强度、高阻尼、良好的锻造性,以及易回收利用等一系列优点。由于镁是密排六方结构,室温塑性差,如何经济地得到组织性能稳定的镁合金变形材一直是摆在广大研究者面前的重大课题。已有研究结果表明,镁合金的塑性变形能力对温度高度敏感,在高于523K时,棱柱滑移面启动,合金塑性大幅改善。因此,研究镁合金在高温变形下组织性能的演变对实际生产具有指导意义。 相似文献
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高温低应力下AZ31镁合金的蠕变性能及蠕变机理 总被引:1,自引:0,他引:1
研究了AZ31镁合金在高温、低应力下的蠕变性能及蠕变机理.结果表明,AZ31镁合金的高温蠕变具有明显的三阶段蠕变特征;随着温度和应力的增加,稳态蠕变速率增加,稳态蠕变速率区域缩短.温度大于420℃、较低应力时,AZ31镁合金的蠕变为晶界扩散控制的COBLE蠕变;较高应力时,与位错攀移控制的WEETMAN蠕变机制相吻合.当温度为320~420℃时,AZ31镁合金的蠕变为滑移控制的位错蠕变.计算了由COBLE蠕变向WEETMAN蠕变转变的临界应力σcr,该应力与P-N力τp在数值上具有如下关系:σcr≈(2~3)τp 相似文献
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为了了解AZ91D压铸镁合金在高温条件下服役的组织演化规律,通过组织观察、力学性能测试、断口形貌分析,研究了180℃时效后镁合金的组织转变、性能变化及其之间的关系.结果表明:AZ91D压铸镁合金在180℃时效后,显微组织由压铸态的非平衡伪共晶组织向固溶合金的平衡态组织转变,其强度和硬度随时效时间的延长先提高后降低,其变化规律与析出相的作用密切相关. 相似文献
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利用Gleeble-1500D热模拟机完成AZ31镁合金高温压缩实验,并将每一组实验均选作为GP模型的训练样本。然后利用处理高度非线性问题的高斯回归技术,借助MATLAB语言编程,预测与训练样本相对应的流变应力,并与ANN模型预测结果进行对比。结果表明,GP模型预测的平均绝对误差为0.39MPa,平均相对误差为0.58%。与ANN模型预测结果相比,其预测精度更高且简单易行,是AZ31镁合金高温压缩实验中参数预测和优化的可行工具。 相似文献
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Magnesium and its alloys applications in automotive industry 总被引:4,自引:1,他引:3
Mustafa Kemal Kulekci 《The International Journal of Advanced Manufacturing Technology》2008,39(9-10):851-865
The objective of this study is to review and evaluate the applications of magnesium in the automotive industry that can significantly contribute to greater fuel economy and environmental conservation. In the study, the current advantages, limitations, technological barriers and future prospects of Mg alloys in the automotive industry are given. The usage of magnesium in automotive applications is also assessed for the impact on environmental conservation. Recent developments in coating and alloying of Mg improved the creep and corrosion resistance properties of magnesium alloys for elevated temperature and corrosive environments. The results of the study conclude that reasonable prices and improved properties of Mg and its alloys will lead to massive use of magnesium. Compared to using alternative materials, using Mg alloys results in a 22% to 70% weight reduction. Lastly, the use of magnesium in automotive components is increasing as knowledge of forming processes of Mg alloys increases. 相似文献
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通过铸造镁合金AZ91D和变形镁合金AZ31B室温环境下应力控制的低周疲劳试验,采用Basquin模型、SWT模型、应变能-寿命模型等模型进行了镁合金低周疲劳的寿命预测。在此基础上,基于连续介质损伤力学的不可逆热力学理论,将镁合金的低周疲劳损伤视为一个不可逆的耗散过程,用熵来反映系统的耗散过程,并以每一次循环的平均应变增量来反映平均应力对材料的影响,提出了一种新的镁合金低周疲劳寿命预测模型。用该模型进行了镁合金的低周疲劳寿命预测,预测结果与实测结果符合较好,同时相比上述其他模型,该模型具有较好的预测效果。 相似文献
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There are many researches on the deformation behavior of wrought magnesium alloys, such as AZ31, AZ80, AZ91, and ZK60 magnesium alloys at different temperatures and strain rates, but few of them focuses on the deformation behavior of AZ41M and ZK60M alloys, especially under the twin-roll casting (TRC) state. Meanwhile, the existing researches only focus on the grain refinement law of the magnesium alloys under deformation conditions, the deformation mechanism has not been revealed yet. The hot compression behavior of AZ41M and ZK60M magnesium alloys under the temperature and strain rate ranges of 250-400 ℃ and 0.001-1 s-1 are studied by thermal simulation methods using Gleeble 1500 machine and virtual simulation using finite element analysis software. Simulation results show that sine hyperbolic law is the most suitable flow stress model for wider deformation conditions. The most reasonable selected deformation conditions of ZK60M alloy is 350 oC/0.1 s-1 for TRC and 350 oC/1 s-1 for conventional casting (CC), while AZ41M alloy is 300 oC/0.01 s-1 for TRC and 350 oC/0.1 s-1 for CC. Deformation behavior and dynamic recrystallization (DRX) mechanism of them are analyzed at the same deformation conditions. The microstructures of AZ41M and ZK60M alloys are observed at different deformed conditions by optical microscopy (OM) and electron back scatter diffraction (EBSD) and it reveals the flow behavior and deformation mechanism of them. Working harden and work soften contribute to the activation of basal, non-basal slip systems which promote DRX. The proposed research reveals the deformation behavior and mechanism of the AZ41M and ZK 60M magnesium alloys and concludes their optimized deformation parameters and processes and provides a theory basis for their manufacturing and application. 相似文献
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综述了国内外AZ31镁合金的研究进展.分别介绍了AZ31镁合金组织、力学性能及变形行为研究现状,讨论了合金元素对AZ31镁合金的影响,并对变形镁合金AZ31耐蚀性的相关研究进行了总结.最后对AZ31镁合金的发展前景进行了分析. 相似文献