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[7-8],从而产生局部高压,能使初生树枝晶破碎,增加了形核质点.这些形核质点在声流的作用下均匀弥散分布于铝熔体中,而且声流有利于使铝熔体的温度场均匀稳定,故凝固时能形成细小,均匀的等轴晶. 表2所示为用电子探针分析仪对普通铸锭和超声铸锭的基体组织进行打点分析得到的主要元素质量分数.由表2可以看出:与普通铸锭相比,在超声外场下α-Al中的Zn元素质量分数增加了22%,Mg元素质量分数增加了54%,Cu...提高了基体相和第二相的形核率,并细化了晶粒和第二相尺寸.声流的搅拌作用能使熔体温度场更加均匀,提高与外界的对流换热能力,并对促进第二相颗粒的弥散分布和清洗表面杂质有着重要的作用. 根据Al-Cu二元合金相图[9],当Cu质量分数为1.75%时,铝合金凝固过程中形成CuAl2的温度为380 ℃,Al2Cu相几乎不溶入其他元素.根据Al-Zn-Mg三元合金相图[9],当Zn质量分数为7.36%,Mg质......
and Engineering, Jilin University, Changchun 130022, China) Abstract: The thermodynamics equilibrium phases of Mg-Al-Ti system were worked out to be Al-Ti intermetallics by computing program of Miedema... composite are obviously enhanced. Key words: Al3Ti intermetallic; Mg-Al-Ti system; Miedema model; thermodynamics equilibrium phases ......
phases which contained Cu, Fe and Mn are small (＜5 μm). Key words: 2099 Al-Li alloy; homogenization process; dendritic structure; secondary phases 铝锂合金具有比强度高和比刚度高,疲劳裂纹扩展速率低和高,低温性能较好等特点,广泛应用于航天航空领域,成为减轻飞行...异的关键.为此,本文作者通过金相观察,扫描电镜,透射电镜以及力学性能分析等方法,研究了不同均匀化温度和时间对2099铝锂合金组织和性能的影响,提出了适合2099铝锂合金的均匀化处理制度,为2099铝锂合金的国产化提供可靠的数据支持. 1 实验方法 实验用2099铝锂合金成分见表1.合金以高纯Al,Mg,Zn和Li,以及Al-Cu,Al-Mn,Al-Zr,Al-Ti和Al-Be中间合金为......
纳米晶Al-Cu-Mg合金的微观组织与力学性能研究 樊建中1,程军胜2,田晓风1,万志永1,肖伯律1,杨滨2 (1.北京有色金属研究总院,国家有色金属复合材料工程技术研究中心,北京,100088;2.北京科技大学新金属材料国家重点实验室,北京,100088) 摘要:以工程实际中应用较广的Al-Cu-Mg铝合金作为研究对象, 用Al-Cu-Mg铝合金气体雾化粉末作为原材料, 通过低温液氮球磨获得纳米晶后, 再经真空热压和热挤压制备了致密的大块体纳米材料. 通过力学性能测试, 挤压态的纳米晶Al-Cu-Mg块体材料抗拉强度达470 MPa, 经过T4处理后, 抗拉强度达到590 MPa, 远远超过常规方法制备的Al-Cu-Mg铝合金抗拉强度. 对纳米晶Al-Cu-Mg块体材料进行微观组织观察, 分析了材料强度提高的原因. 关键词:铝合金; 纳米块体; 低温球磨; 力学性能; [全......
> Microstructure and mechanical properties of enhanced solution treated 7075 and 2024 aluminum alloys Abstract: The effects of enhanced solution of second phases... the multi phase eutectic temperature without the formation of overheated microstructure, and improve the second phase solution. In contrast to alloy 2024, the second phases in alloy 7075 can dissolve more......
HRTEM studies of aging precipitate phases in the Mg-10Gd-3Y-0.4Zr alloy王冬舒1,李德江1,谢艳才1,曾小勤21. National Engineering Research Center of Light Alloys Net Forming,School of Materials Science... mechanisms in the Mg-RE alloys. In order to understand the formation of precipitates during aging at 225 oC in a Mg-10Gd-3Y-0.4Zr alloy(GW103K) with high strength and heat resistance, a high-resolution......
HRTEM studies of aging precipitate phases in the Mg-10Gd-3Y-0.4Zr alloy王冬舒1,李德江1,谢艳才1,曾小勤21. National Engineering Research Center of Light Alloys Net Forming,School of Materials Science... mechanisms in the Mg-RE alloys. In order to understand the formation of precipitates during aging at 225 oC in a Mg-10Gd-3Y-0.4Zr alloy(GW103K) with high strength and heat resistance, a high-resolution......
Trans. Nonferrous Met. Soc. China 26(2016) 2800-2809 Localized dissolution initiated at single and clustered intermetallic particles during immersion of Al-Cu-Mg alloy in sodium chloride solution... characterized in order to provide input data for microscale corrosion models of Al-Cu-Mg alloys. 2 Experimental Cold-rolled sheet AA2024-T3 aluminium alloy with thickness of 1.6 mm (4.45% Cu, 0.28% Fe, 1.34% Mg......
in magnesiumoxychloride cement prepared with MgCl2 solu-tions of different concentrations are mainly5.1.8 and Mg(OH)2.The relationship betweenthe ratio of the hydration phases and thestrength of the cement was calculated...HYDRATION PHASES IN MAGNESIUM OXYCHLORIDE CEMENT PASTE AND THEIR INFLUENCE ON THE STRENGTH INDEX崔可浩,崔崇,易海云摘 要:<正> The study is for the purpose......
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