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1.
稀土铝锂合金各向异性的指数叠加法研究   总被引:1,自引:0,他引:1  
魏齐龙  陈铮  赵志龙 《稀土》2002,23(3):21-25
本文采用指数叠加法研究了 2 0 90铝锂合金的各向异性和稀土 Ce的作用。研究结果表明 :在 2 0 90铝锂合金中 ,T1 相在纵向强化作用最小 ,在横向最大 ,在短横向居中 ;而δ′相则在时效早期增强各向异性。稀土 Ce对铝锂合金的各向异性的影响有双重性 :一方面 ,Ce加强了铝锂合金的形变织构 ,即增强各向异性 ;另一方面 ,Ce主要减小了 T1 相对横向的强化贡献 ,并减小了δ′相在不同方向强化贡献的差别 ,从而在一定程度上减弱各向异性。  相似文献   

2.
蒋呐 《铝加工》2003,26(5):8-11
通过力学性能测试和断口形貌观察,研究了1420铝锂合金冷轧薄板的各向异性及其在时效过程中的演化规律。结果表明,1420铝锂合金具有明显的各向异性,在120℃时效条件下,随着时效时间延长,各向异性增加。最后,初步探讨了该合金各向异性的主要形成机理。  相似文献   

3.
Aluminum-lithiumalloy 2195 is a kind of poten-tial material for innovative manufacturing of key partsin aviation and aerospace .The alloys display a superi-or strengthto weight ratio than any other conventionalaluminumalloy under the applied condition .If the al-loyis properly processed ,it can perform higher frac-ture strength in cryogenic temperature than at roomtemperature[1],so its promising future in the nationaldefense industry can be predicted definitely . Howev-er ,the alloy exhibits s…  相似文献   

4.
The effect of Y-base rare earth alloy in ultra-high hardfacing was observed by means of OM, SEM and XRD. Precipitated carbide can be metamorphosed and spheroidized in surfacing by adding Y-base rare earth alloy, which contributes to the increase of precipitated carbide. Rare earth combined with oxygen and sulfur can improve the morphology of slag inclusion as well as purify surfacing. The result shows proper rare earth alloy in surfacing can fine its microstmcture, improve hardness and impact toughness.  相似文献   

5.
For the purpose of decreasing the applied limitation resulting from the anisotropic mechanical property of Al-Li alloy 2195, this study employed a complex heat treatment process, involving the pre-tension, thermo-infiltration of the rare earth element Ce, solution treatment, and artificial aging technology. The results indicate that the infiltration of rare earth element Ce benefits the abatement of anisotropy of Al-Li alloy 2195 sheet, in contrast with that of the normal heat treatment process. The gradient of the Vickers-hardness decreases at least 50% through the thickness, and the tensile strength in the rolling direction also increases significantly. If Ce was infiltrated into the alloy under the optimum pre-deformation, the yield strength (σ0.2) increased by 30 MPa while the tensile strength (σb) enhanced by 25 MPa compared to the rare earth free samples. Meanwhile, the fractography illustrated that the fracture surface of the sample became more desirable.  相似文献   

6.
EffectofRareEarthMetalsonMicrostructureofDirectionalSolidifiedAl-3LiAlloy¥WangLi-Min;DangPing;DuFu-Ying;ZhaoMin-Shou(Changchu...  相似文献   

7.
Magnesiumalloysarewidelyusedinweaponin dustry,spacenavigationandhavegoodpotentialof applicationanddevelopmentindailycommunication facilitiesduetotheirpropertiesoflightweightandhighstrength[1].Appliedasstructuralmaterials,mag nesiumalloysmayeasilycrackduet…  相似文献   

8.
稀土铈对化学沉积Co-Ni-B合金镀层结构和性能的影响   总被引:5,自引:3,他引:5  
宣天鹏  章磊  黄芹华 《稀有金属》2003,27(3):399-402
研究了稀土铈对化学沉积Co-Ni-B合金层化学组成、结构和性能的影响。结果表明:微量稀土铈的加入提高了镀层中钴的含量,降低了镍和硼的含量;使镀层由非晶态转变为品态;稀土铈也明显地提高了镀层的显微硬度,在一定的范围内,镀液中稀土铈添加量越多,镀层的铈含量和显微硬度也越高;稀土铈还提高了镀层的饱和磁化强度,降低了剩余磁化强度和娇顽力,含铈镀层显示出了良好的软磁性能。  相似文献   

9.
Asoneoftheexternalparameterswhichaffectthematerialproperties ,theeffectofmagneticfieldonatomshasbeenstudiedandappliedinmanyareasandmakesmuchprogressinmanysubjects ,suchassolidphysics ,surfacephysics ,andplasmaphysics .ThematuretechnologyMCZinsemiconductor…  相似文献   

10.
The Ni-based self-fluxing alloy coating containing RE was acquired by the technique of vacuum melting on the hypoeutectoid steel (Fe-0.45% C) matrix. By X-ray diffraction, SEM and EDX, the microstructure and phase structure of section of coating and the microstructure near the interface between coating and matrix were investigated, and the effect of RE on microstructure of coating was also discussed. The results show that the microstructure of the NiCrBSi alloy coating is composed of Ni-based solid solution and a lot of massive, globular and needle secondary phases CrB, Ni3B, Cr7C3, Cr23C6 among the solid solution. The metallurgical binding between steel matrix and coating is realized. RE makes needle phase of alloy coating vanish. New phases of NiB and Cr6.5Ni2.5Si are precipitated from alloy coating, and secondary phases of alloy coating are sphericized. Consequently, RE also hinders the diffusion of Ni, Cr and Si atoms from coating to matrix and Fe atoms from matrix to coating, holds back the dilution of Fe for NiCrBSi alloy coating, and assures the chemical composition of the alloy coating.  相似文献   

11.
Zn Alalloyisoneofalloymaterialswide lyusedinindustry .Zn 5Aleutecticalloyisnotonlyextensivelyusedasdie castingalloy ,hotplatingandsprayingalloy ,butobtainsrecognitioninsuperplasticshapingandsuper plastictheoreticalresearchesowingtoitsex traordinarysuperpla…  相似文献   

12.
用ODF方法研究了Al Li合金形变热处理的织构、织构特征及其变化规律。实验在这种fcc结构的Al Li合金板中发现了{111}//ND纤维织构,最大f(g)大于3。同时,对其形成机制进行了分析讨论。  相似文献   

13.
TiN coatings were deposited on polished substrates of W18Cr4V high speed steel by means of vacuum arc ion plating. The effect of cerium on adhesion between TiN coating and substrate was studied. The microstructures and composition of TiN coatings were also investigated by means of scanning electron microscope (SEM), Auger electron spectroscopy (AES), and X-ray diffraction (XRD) technique. It was found that cerium is an effective modifying agent and the addition of suitable amount of cerium to TiN coatings can produce relatively excellent properties such as micro-hardness, wear resistance, oxidation resistance and porosity. The experimental results show that the added cerium in TiN coatings makesa contribution to form the preferred direction along with a (111 ) or (222) close packed face, which may be one of the reasons that improves some properties mentioned above.  相似文献   

14.
Effect of Rare Earth on Microstructure of γ-TiAl Intermetallics   总被引:3,自引:0,他引:3  
The rare earth (RE) elements (Ce, La) were added to binary Ti-47% Al alloys (atomic fraction) by Induction Skull Melting. The element Ce of 1.0 atomic percent was added individually, and La of 0.2 atomic percent was added individually. This article studied the influences of rare earth metal (Ce, La) on microstructure of as-cast TiA1 based alloy by XRD, SEM, EMPA and TEM measurement methodology. The results show that most of rare earth-rich phases (AlCe, Al-La) are uniformly distributed in grain boundary in the shape of discontinuous network, and some particles of rare earthrich phases within the grains are mainly ellipsoids. In addition, rare earth element can obviously refine the grain size and the lamellar thickness of as-cast TiAl based alloy samples. The grain size of Ti-47Al-1.0Ce-0.2La alloy reaches about 30~80μm, and the lameUar thickness of its γ phase and α2 phase are less than 200 and 20nm, respectively.  相似文献   

15.
Friction and Wear Characteristics of Mg-Al Alloy Containing Rare Earths   总被引:3,自引:4,他引:3  
The influence of rare earth on the friction and wear characteristics of magnesium alloy AZ91 and AM60 were studied. The results show that the wear resistance properties of rare earth magnesium alloys are better than those of matrix alloy under the testing conditions. The anti-wear behaviour of AZ91 alloy is much better than that of AM60 alloy. In dry sliding pmcess, magnesium alloys undergo a transition from mild wear to severe wear. The addition of rare earths refine the structure of alloys, improve the comprehensive behaviors of magnesium alloys,increase the stability of oxidation films on worn surfaces,enhance the loading ability of rare earth magnesium alloys,and delay the transition from mild wear to sevre wear effectively.  相似文献   

16.
马光  贾志华  李银娥  王轶 《稀有金属》2005,29(4):391-396
根据近年来钯基氢净化材料的研究状况,综述了添加稀土元素对钯基氢净化材料的影响。重点从稀土元素对钯吸氢后形成α相向β相的转变、透氢性能、力学性能以及有害杂质污染的抵抗能力等4个方面进行了阐述。说明添加稀土元素,特别是Y可明显改善钯膜的性能,为低廉、高效获得高纯氢提供了良好的途径。  相似文献   

17.
Study on Ignition Proof AZ91D Magnesium Alloy Chips with Cerium Addition   总被引:4,自引:1,他引:4  
The effect of Ce on ignition point of AZ91D magnesium alloy chips was studied. For the AZ91D and the AZ91D-xCe magnesium alloys, changing the sizes of the chips in the range of 58 - 270 μm has a limited influence on ignition point, however, the shift of the content of Ce has much effect on ignition point. Increasing the Ce content, x from 0.15 to 0.25, the ignition point increases with increasing of Ce; however, x from 0.25 to 0.45, the ignition point decreases with increasing of Ce. By the addition of Ce of 0.25 %. the ignition point is raised by 43℃.  相似文献   

18.
采用力学性能测试、光学显微镜(OM)、X射线衍射(XRD)及透射电镜(TEM),研究了 5 mm厚度2195铝锂合金挤压板材和后续2 mm厚度冷轧薄板T8时效态力学性能及微观组织的演化.研究结果表明:相同T8时效(3.8%预变形,148℃,38 h)条件下,5 mm厚度挤压板材抗拉强度及屈服强度比后续2mm厚度冷轧薄板...  相似文献   

19.
ZAalloysbelongtocastzincalloyfamilydevelopedbyCanadianandAmericanresearchersinmid1970s.ZAalloysareofgoodcastingandprocessingpropertiesandarewidelyusedindifferentfields[1].HypoeutecticZZn41alloy,asanimportantmemberofZAalloyfamily,isofgoodcastabilityandthusi…  相似文献   

20.
Effect of cerium on the microstructure and electrochemical performance of the Ti0.25V0.35-xCexCr0.1Ni0.3(x=0,0.005)electrode alloy was investigated by X-ray diffraction(XRD),field emission scanning electron microscopy/energy dispersive X-ray spectrometry(FESEM-EDS),and electrochemical impedance spectroscopy(EIS)measurements.On the basis of XRD and FESEM-EDS analysis,the alloy was mainly composed of V-based solid solution with body-centered-cubic structure and TiNi-based secondary phase.Ce did not exist in two phases,instead,it existed as Ce-rich small white particles,with irregular edges,distributed near the grain boundaries of the V-based solid solution phase.Discharge capacity,cycle stability,and high-rate discharge ability of the alloy electrode were effectively improved with the addition of Ce at 293 K.It was very surprising that the charge retention was abnormal with larger discharge capacity after standing at the open circuit for 24 h.EIS indicated that addition of Ce improved the dynamic performance,which caused the charge transfer resistance(RT)to decrease and exchange current density(I0)to increase markedly.The exchange current density of the electrochemical reaction on the alloy surface with Ce addition was about 2.07 and 3.10 times larger than that of the alloy without Ce at 303 and 343 K,respectively.The diffusion coefficient of hydrogen(D)in the bulk alloy electrode decreased with addition of Ce,but it did not decrease so much,and the apparent activation energy(△rH)was far higher than that of the AB5 type alloy.  相似文献   

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