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研究了在5A01合金基础上添加0.2%Sc和0.3%Sc后合金的显微组织、力学性能、腐蚀性能及焊接性能。结果表明,微量Sc的加入,初生Al3Sc或Al3(Sc,Zr)粒子可成为有效的非均质晶核,大大地细化合金的铸态晶粒,次生Al3Sc或Al3(Sc,Zr)粒子,能有效地钉轧位错和亚晶界,稳定亚结构并强烈抑制合金的再结晶。因此,加入Sc后的试验合金基体及焊接强度提高,腐蚀性能和焊接性能与5A01合金相当甚至更好。 相似文献
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通过向合金中单独或联合添加微量的Sc、Zr、Ti,研究了Sc、Zr、Ti复合合金化对Al-5Mg合金微观组织、再结晶抗力及力学性能的影响.研究结果表明合金中单独添加0.2%Sc,使合金的再结晶抗力、硬度和强度明显增加而塑性明显下降,但对合金没有晶粒细化效果.Sc、Zr复合合金化明显改善了Sc对晶粒的细化能力和再结晶抗力,合金的强度和硬度也进一步增加,但对塑性的影响不大.添加0.036%Ti进行Sc、Zr、Ti复合合金化使合金具有最佳的晶粒细化效果和再结晶抗力,但对合金的力学性能影响不大.原因在于Sc、Zr、Ti复合合金化降低了Al-Al3Sc共晶点,而且Zr、Ti可以代替部分Sc形成Al3Sc1-xZrx或Al3Sc1-xTix复合粒子,有利于凝固过程中形成与α-Al具有良好晶格匹配性的一次Al3Sc1-xZrx或Al3Sc1-xTix复合粒子及挤压和退火过程中二次复合粒子的析出.这些大量的、弥散分布的、与基体共格的粒子可以有效地阻止位错的运动和亚晶界的迁移,从而产生良好的细晶强化、弥散强化和亚结构强化效果. 相似文献
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过渡族元素Zr,Ti对Al—Sc合金高温力学性能影响 总被引:1,自引:0,他引:1
在Al-0.35Sc合金中加入不同含量的微量过渡族元素Zr,Ti,采用正交实验测定了这些含Zr,Ti元素的Al-0.35Sc合金的高温(270℃)力学性能,研究了Zr,Ti加入量、时效温度、时间对合金的高温力学性能的影响。并应用透射电镜,观察了微观组织,分析高温强化机理,观察表明,加入Zr,Ti的合金中第二相粒子细小。270℃温度条件下,Al-0.35Sc-Zr-Ti合金的高温力学性能高于Al-0.35Sc合金。高温状态下,共格强化、亚晶强化、晶界强化三种机理共同起作用。 相似文献
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在Al-0.35Sc合金中加入不同含量的微量过渡族元素Zr,Ti,采用正交实验测定了这些合Zr,Ti元素的Al-0.35Sc合金的高温(270℃)力学性能.研究了Zr,Ti加入量、时效温度、时间对合金的高温力学性能的影响.并应用透射电镜,观察了微观组织,分析高温强化机理,观察表明,加入Zr,Ti的合金中第二相粒子细小.270℃温度条件下,Al-0.35SC-Zr-Ti合金的高温力学性能高于Al-0.35Sc合金.高温状态下,共格强化、亚晶强化、晶界强化三种机理共同起作用. 相似文献
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Mg-Al-Zn-Mn合金在NaCl溶液中的接触腐蚀行为 总被引:1,自引:0,他引:1
研究了作为牺牲阳极材料的Mg-Al-Zn-Mn合金在NaCl溶液中与A3钢、302不锈钢和紫铜偶按时的接触腐蚀行为,探讨了溶液中Cl-浓度变化,以及电偶对中阴极金属材料和阴阳极面积比Ac/Aa不同对镁合金阳极电偶电流密度jqMq的影响。结果表明,Cl-浓度较高时,jqMq随浓度增大明显增大,阴极金属材料和阴阳极面积比不同在Cl-浓度高于0.010mol/L时对jqMq有较大影响,jqMq与Ac/Aa成正比关系.电偶电势Eg随溶液中Cl-浓度增大向负向变化。 相似文献
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The microstructure and the phase composition of as-cast Al–Mg–Mn–Sc–Zr alloy samples are studied by electron microscopy and electron-probe microanalysis. The processes of solidification and melting of this alloy are described. The temperature dependence of the kinematic viscosity of the Al–Mg–Mn–Sc–Zr melts is studied during heating and subsequent cooling of the samples. The measurement results are used to determine the temperature at which inherited microheterogeneities in the melts are destroyed irreversibly. 相似文献
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采用维氏硬度测量、室温拉伸性能测试和显微组织结构分析,研究了不同时效制度下Al-Zn-Cu-Mg-Sc-Zr合金的力学性能、腐蚀性能和显微组织。结果表明,合金具有显著的时效硬化效应,随时效温度的升高,合金达到时效硬度峰值的时间缩短。合金适宜的时效制度为120℃/24 h。此时,合金的抗拉强度、屈服强度、伸长率和维氏硬度分别为696 MPa、654 MPa、11.1%和211.2 HV。合金中主要强化相为GP区和η′相,主要强化作用为沉淀强化及弥散强化。时效过程中Al3Sc和Al3(Sc,Zr)质点表现出较强的热稳定性;合金抗晶间腐蚀能力随时效时间的延长而增强。 相似文献
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In order to enhance the weldable thickness and tensile properties of dissimilar ultra-thin Al/Mg alloy sheets, ultrasonic-assisted friction stir welding (UaFSW) was performed. The addition of ultrasonic produces three benefits. First, a sound joint with smooth surface appearance was achieved. Next, weldable thickness and mixing degree of Al/Mg alloys were improved based on better material flow. Finally, continuous intermetallic compound (IMC) layer in the conventional joint was broken into small pieces, delaying crack propagation. Maximum tensile strength of the UaFSW joint reached 130?MPa, which was much more higher than 102?MPa of the conventional joint. It is concluded that UaFSW has a huge potential to join dissimilar alloys, especially those with the formation of IMCs. 相似文献
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Dai Xiaoyuan Xia Changqing Li Yangyong Sun Zhenqi 《中国稀土学报(英文版)》2006,24(5):635-635
The microstructures of Al-Zn-Mg-Cu-Zr al- loys with minor Sc were studied by using optical microscope(OM), scanning electron microscope (SEM) and transmission electron microscope(TEM). The tensile mechanical properties and electric conductivity of the studied alloys under different treatment conditions were tested. The results show that adding minor Sc can greatly fines the grain size of the Al-Zn-Mg-Cu-Zr alloy ingots and obviously improves the tensile properties and electric conductivity of the alloys. The strengthening mechanism is considered as fine grain strengthening, sub-structure strengthening and dispersion strengthening by Al3 (Sc, Zr). 相似文献
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《Canadian Metallurgical Quarterly》2013,52(2):136-141
AbstractThe effect of minor Zr and Ti elements on microstructures and properties of Al–8·6Zn–2·5Mg–2·2Cu alloys was investigated. The results show that there is no significant change in the grain size by simultaneous addition of Zr and Ti as compared to individual additions of Zr or Ti to Al–8·6Zn–2·5Mg–2·2Cu alloy. The ability of restraining recrystallisation of Al–8·6Zn–2·5Mg–2·2Cu–0·16Zr–0·04Ti alloy is weaker than that of alloy Al–8·6Zn–2·5Mg–2·2Cu–0·16Zr alloy, since Ti and Zr have a poisoning interaction. The corresponding tensile properties, hardness and stress corrosion cracking resistance of the Al–8·6Zn–2·5Mg–2·2Cu–0·16Zr alloy were decreased by addition of Ti. 相似文献
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利用光学显微镜、透射电子显微镜、显微硬度计和万能拉伸试验机等分析手段,表征了Al?Zn?Mg?Cu?Zr?(Sc)合金搅拌摩擦焊(FSW)接头的显微组织和性能,探究了Sc元素对改善超高强Al?Zn?Mg?Cu?Zr合金焊接性能的作用机制。结果表明:Al?Zn?Mg?Cu?Zr?(Sc)合金焊接接头具有相似的组织特征,焊核区为动态再结晶组织,由细小均匀的等轴晶组成,包含较高密度的位错线,大部分时效析出相回溶;热力影响区晶粒被拉长,位错密度更高,残留的时效析出相显著粗化;热影响区保留与母材相同的晶粒形态,大部分时效析出的η'相发生长大,少部分粗化成η相。添加质量分数0.17%的Sc,可以使合金FSW接头抗拉强度提升43 MPa,屈服强度提升23 MPa,断后伸长率改善2.3%,焊接系数达到74.1%。Al3(Sc,Zr)二次析出相可以强烈抑制位错、亚晶界、晶界的移动,细化晶粒的同时保留大量的亚结构,且自身可发挥Orowan弥散强化作用。因此,可通过细晶强化、亚结构强化和弥散强化三种方式显著提高合金FSW接头的力学性能。 相似文献