共查询到20条相似文献,搜索用时 62 毫秒
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分析了在铸钢中加入微量稀土元素后,稀土元素对铸钢的性能影响。试验结果表明,合适的稀土添加量,可以提高铸钢的韧性、硬度及耐磨性;金相组织分析表明,稀土元素的添加能较好的细化晶粒并改善夹杂物的数量及形态,从而提高其综合力学性能。 相似文献
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利用电子探针分析技术,对在AuCuNi金基合金中添加的稀土元素的 研究,发现稀土元素在AuCuNi合金中产生了新相。微量稀土元素加入后,起到了强化合金和提高耐磨性的作用,且电接触性能优良。 相似文献
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本文介绍一种新的有关植物中的微量稀土元素的分析方法。3个品种的土生植物(杉木、竹和茶树)中的微量镧系元素经过萃取与反萃取分离富集后,我们采用电感耦合等离子质谱仪成功地进行测定。本文详细地研究了各种条件对测定结果的影响。利用本方法测定植物中的微量稀土元素,6次测定结果的相对标准偏差低于5%。由于没有稀土元素的植物标准试样,为了检验本方法的准确度,我们也用同位素稀释法测定茶树中的稀土元素。两种方法所得到的结果十分一致,证明用本方法所得的结果是正确的。 相似文献
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在耐磨铸钢的钢液中添加适量的稀土元素有利于提高耐磨铸钢的强韧性及抗冲击性,同时还能优化耐磨铸钢的铸造性能。本文简单介绍了稀土元素,以及稀土元素在耐磨铸钢中的作用机理,分析了不同含量的稀土元素对耐磨铸钢的组织及性能的影响。 相似文献
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本文叙述了国内外镁合金稀土元素合金化的研究进展;讨论了稀土元素对镁合金熔体、组织和性能以及耐腐蚀性的影响;分析了镁稀土合金研究存在的问题;指出镁稀土合金是镁合金研究的重要发展方向。 相似文献
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Improvement of Ductility of Powder Metallurgy Titanium Alloys by Addition of Rare Earth Element 总被引:1,自引:0,他引:1
Yong LIU Lifang CHEN Weifeng WEI Huiping TANG Bin LIU Baiyun HUANG 《材料科学技术学报》2006,22(4):465-469
Ti-4.5Al-6.0Mo-1.5Fe, Ti-6Al-1Mo-1Fe and Ti-6Al-4V alloys were prepared by blended elemental powder metallurgy (PM) process, and the effects of Nd on the microstructures and mechanical properties were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). It was found out that the addition of Nd increased the density of sintered titanium alloys slightly by a maximum increment of 1% because small amount of liquid phase occurred during sintering. The addition of Nd shows little effect on the improvement of tensile strength, while the elongation is significantly improved. For example, the elongation of Ti-4.SAl-6.0Mo-1.5Fe can be increased from 1% without addition of Nd to 13% at a Nd content of 1.2 wt pct. 相似文献
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A new type of abrasion-resistant cast boron steel was developed based on the service conditions of the guide roller in the high-speed steel wire-rod mill. The lath martensite was its matrix and the broken Fe2B and dispersive distributed TiB2 were its wear resistant skeleton. The tensile strength, hardness, and impact toughness of cast boron steel quenched at 1000°C excel 750 MPa, 54 HRC, 14 J/cm2, respectively. The guide roller made of this steel has high strength and wear resistance and excellent thermal fatigue resistance and it is reliable to use in the high-speed steel wire-rod mill. Its service life is 1.133 times longer than that of cast high chromium nickel alloy steel and corresponding to that of the sintered-carbide. 相似文献
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Xiangting DONG Guangyan HONG College of Materials Chemical Engineering Changchun University of Science Technology Changchun China Key Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China 《材料科学技术学报》2005,21(4):555-558
A series of rare earth hydroxide and oxide nanoparticles have been prepared by precipitation method with alcohol as the dispersive and protective reagent. Transmission electron microscope (TEEM) images indicate that the particles are spherical in shape and smaller than 100 nm in size. The crystallite sizes of cubic Ln2O3 have lanthanide shrinking effect, while average crystal lattice distortion rates possess lanthanide swelling effect. The diffraction peak intensity of heavy rare earth oxide nanometer powders is remarkably stronger than that of light rare earth oxide nanometer powders. The variation of diffraction intensity with atomic number presents an inverted W type, forming a double peak structure. Fourier transform infrared (FTIR) spectrums reveal that Ln2O3 nanopowders have higher surface activity than that of ordinary Ln2O3 powders. The UV-vis spectra show that Ln-O bond of these particles is slightly blue-shifted, and its absorption intensity decreases. 相似文献
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稀土氧化物纳米材料的合成与制备近年来已成为国内外学者研究的一个热点。本文介绍了国内外稀土氧化物纳米材料制备及合成方法的研究进展,并对稀土氧化物纳米材料的制备方法进行了分类。同时,综合比较了各自的优点和缺点,并对各种制备方法在各个领域的应用前景进行了一定的展望。 相似文献
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简要介绍了稀土发光材料的发光原理和八种制备方法,包括传统的高温固相反应法溶胶-凝胶法、水热合成法、低温燃烧合成法、化学沉淀法、微波辐射法、电弧法、CO2激光加热气相沉积合成法,总结了每种制备方法的优缺点,并对稀土发光材料的应用和发展前景进行了展望。 相似文献
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复合稀土掺杂α-Sialon的氧化行为 总被引:3,自引:0,他引:3
对组份为(Nd0.18Y0.18)Si10.38Al1.62O0.54N15.46和(Nd0.18Yb0.18)Si10.38Al1.62O0.54N15.46的复合稀土掺杂α-Sialon材料在1200~1400℃温度范围内的氧化行为进行了研究.样品由热压工艺制备.研究结果表明,在1200和1300℃氧化20h的材料表面存在择优取向的含Nd和Y(或Yb)-硅酸盐晶粒.随氧化温度的提高,氧化表面由相对致密的硅酸盐氧化层软化形成气泡直至出现明显的透明玻璃相.文中还对氧化过程中表面形成的物相进行了讨论. 相似文献
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