共查询到19条相似文献,搜索用时 156 毫秒
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熔炼制备不同稀土加入量的Al-3.0Mg-xRE(质量分数/%,x=0,0.12,0.31,RE为La+Ce)合金,研究了该合金的显微组织、硬度和拉伸性能在冷拉拔过程中的演变规律.结果表明:冷拉拔过程中,试验合金的晶粒拉长,第二相拉长并破碎成细小粒子,并在晶界和枝晶界处逐渐聚集呈线状分布,Copper{112}<111>型变形织构强度逐渐增高;随着变形量的增大,合金的强度呈线性增大,塑性降低,显微硬度增大;适量稀土(0.12%)的加入能够改善合金组织与力学性能,但过量稀土(0.31%)的加入会导致合金中第二相数量和尺寸的增加,从而降低合金的力学性能.冷拉拔后,Al-3.0Mg-0.12RE合金中第二相的长度最小,数量最少,变形织构强度最高,力学性能最优. 相似文献
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利用WK-Ⅱ型非自耗真空电弧炉熔炼制备AlNiFeCuCoCrVx(x=0,0.1,0.2,0.3,0.4,0.5,原子比)高熵合金,研究了其显微组织和力学性能。结果表明:试验合金的组织均为典型树枝晶结构,由面心立方(FCC)结构固溶体、体心立方(BCC)结构固溶体和金属间化合物相组成,添加钒元素后析出了Fe_2AlV相,该相主要分布于枝晶中;随着钒含量的增加,合金的硬度先增后降再增;添加钒对合金的压缩性能不利,合金的抗压强度随钒含量的增加先降后增再降。 相似文献
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采用真空电弧熔炼制备β型Ti-xMo(x为质量分数/%,3~24)合金,并进行950℃×20 min均匀化处理,随后分别水冷和炉冷至室温,通过内耗测试结合物相和微观结构分析,研究了钼含量和冷却方式对该合金点缺陷弛豫的影响。结果表明:炉冷和水冷Ti-xMo合金中均出现2个Snoek型驰豫峰,炉冷Ti-xMo合金的弛豫峰随钼含量的变化特征与水冷合金相似。2种冷却方式下Ti-xMo合金在加热时的低温峰峰高随钼含量的增加而增大,但峰温几乎不变,峰高的增大与β相和间隙氧原子含量的增多有关;除Ti-3Mo合金外,其余合金高温峰的峰高和峰温都随钼含量增加而增大,峰高和峰温的增大与钼和氧的相互作用增强有关。 相似文献
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Xianghong Wang Yang Sheng Zhou Xiaojie Hu Hongwei 《Russian Journal of Nondestructive Testing》2021,57(4):281-290
Russian Journal of Nondestructive Testing - The existence of long period stacking ordered (LPSO) strengthening phases greatly improves the mechanical properties of Mg alloys, such as tensile... 相似文献
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在分析相变温度和显微组织的基础上,采用低频扭摆仪研究了镍-镓-铁系铁磁性形状记忆合金的阻尼性能与应变振幅、频率及温度的关系.结果表明:Ni52Ga27Fe21合金的马氏体相变为热弹性马氏体相变,特征温度Ms、Mf、As、Af分别为69.3℃,60.2℃,93.6℃,102.6℃,室温下组织为板条状马氏体;镍-镓-铁系合... 相似文献
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Electron diffraction technique for identifying structure types of martensite in β-Hume-Rothery alloys is described. It includes determination of the stacking sequence of the martensite of the basal planes, differentiation of the long-range ordering in martensite inherited from its parent phase (A2 type disordered; B2 type ordered; and DO3, or Heusler, type ordered), and distinguishing between normal-type and modified-type martensite. In addition to the 18R1-type martensite, 12R, 6R, and 2H martensites were found in quenched Cu-Zn-Al alloys using this technique. 相似文献
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FCC metals and alloys are frequently used in cryogenic applications, nearly down to the temperature of absolute zero, because of their excellent physical and mechanical properties including ductility. These materials, often characterized by the low stacking fault energy (LSFE), undergo at low temperatures three distinct phenomena: dynamic strain ageing (DSA), plastic strain induced transformation from the parent phase (γ) to the secondary phase (α′) and evolution of microdamage. The FCC-BCC phase transformation results from metastability of LSFE metals and alloys at very low temperatures. The phase transformation process leads to creation of two-phase continuum where the parent phase coexists with the inclusions of secondary phase. Such heterogeneous material structure induces strong strain hardening related to two distinct mechanisms: interaction of dislocations with the inclusions and increase of tangent stiffness as a result of mixture of two phases, each characterized by different parameters. The strain hardening model is based on micromechanics considerations (first mechanism) and on the Hill concept (1965) including the Mori-Tanaka (1973) homogenization scheme (second mechanism). Identification of parameters of the constitutive model is based on the available experimental data. The model is used to describe phase transformation in rectangular beams subjected to elastic-plastic bending at cryogenic temperatures. Several examples of rectangular beams with FCC-BCC phase transformation induced functionally graded (FGM) microstructure are presented. 相似文献