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针对Ti-Mn基储氢合金循环稳定性差这一问题。提出了一关于Ti-Mn基储氢合金循环稳定性的简易模型,并引入两个表示储氢合金本征属性的因子;活化特征因子β和容量衰减因子A。采用该模型可以描合金活化与容量衰减的全过程。实验测量了Ti0.26Zr0.07V0.21Mn0.1Ni0.3Cr0.03和Ti0.07V0.19Mn0.1Ni0.3Cr0.05合金的活化与充放电循环过程,理论与实验有较好的吻合关系。 相似文献
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近年来具有大贮氢容量材料的开发日益受到重视 ,吸氢容量可达 3% (质量 )以上的Ti3Al便是其中之一。但是Ti3AlHx 过分稳定 ,也就是说为其实用化的放氢温度太高。因此 ,降低这类合金的放氢温度就显得非常重要 ,近年来许多研究者研究了一些替代元素对于Ti75-xAl2 相似文献
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Al—Zn—Li—Mg—Cu合金在433K的时效行为 总被引:3,自引:0,他引:3
采用透射电镜(TEM)和Vickers硬度计研究了Al-Zn-Li-Mg-Cu合金在433K的人工时效行为,结果表明,在等温时效动曲线上存在双阶硬化行为。第一阶段硬化起因子合金基体上沉淀析出的δ′相(AlLi) 时效强化效果来自δ′相;随着时效的进行,到达第二时效硬化峰,在合金基体上除了δ′相外,大量析出一种具有准晶结构的沉硬化相(命名为X相),此时,时铲强化效果来处自δ′相和X相,在X相的周围存在无δ′相析出区,表明X相含有Li原子,X相呈棒状,棒的长轴与基体的<110>Al方向一致,EDS测试表明,X相富集Cu,Zn和Mg。 相似文献
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采用滴落法研究了在1758K条件下Ti-Al合金的表面张力。同时采用Butler模型和几种改进的理想溶液模型理论计算Ti-Al合金表面张力。结果表明,Ti-Al合金的表面张力随着Al含量的增加而减小,实验结果和采用Butler模型以及改进理想溶液模型理论计算的结果相一致。Al原子主要分布在熔体的表面,而钛由于具有高的表面张力主要分布在熔体的内部。同时也讨论了表面活性元素硫对Ti-Al合金表面张力的影响。结果表明硫对合金表面张力影响很大。随着硫的增加,合金表面张力降低。硫在表面上的浓度高于内部。硫在Ti-Al合金中的吸附属于正吸附。 相似文献
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研究了低温熔盐中电镀Al-Ti和Al-Mn合金的方法,以及镀层的组成、结构和性能。探讨了熔盐离子浓度、搅拌等因素对镀层成分、结构及表面状态的影响。研究结果表明,影响镀层中合金元素含量的主要因素是熔盐中合金离子的浓度。Al-Mn合金中含Mn量在25-40%(质量分数)时,呈非晶态结构。电化学测试及腐蚀试验结果表明,所得到的Al-Ti和Al-Mn合金镀层具有优异的耐蚀性。 相似文献
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选取三种热力学模型(规则溶液,LFG,KRC模型)计算了Fe-Mn-Cr高碳四元合金的马氏体相变驱动力和M温度,KRC模型计算结果与实测值最为接近,LFG模型计算结果和实验值相差较大。 相似文献
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Activities of binary baths with 1% solute as standard states 总被引:1,自引:1,他引:0
1 INTRODUCTIONThecompositionsofalloysarealmostpresentedasmolarfractionsin generalthermodynamicshand bookandinthethermodynamicformulae ,anditscor respondingactivitiesareexpressedasRaoultianactivi tieswhosestandardstatesare puresubstances[1] .However ,massfra… 相似文献
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Colors were generated by preferential oxidation of the metals in coloring hot dip galvanization process,and the evolution of temperature field during colling after hot dip would be responsible for the coloration results directly.Tht influences of bath temperature and velocity of steel stripmoving on temperature field of the strip were calculated in continuous coloring hot dip galvanization process by means of the ANSYS/Thermal module.The factors were considered including convection heat transfer,latent heat during cooling,and heat radiation in calculation.The effects of temperature field on coloration of sheet steel samples were investigated. 相似文献
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In this work, low-grade copper sulfide mine has been treated by the bioleaching process using native cultures of Acidithiobacillus ferrooxidans. The bioleaching experiments were carried out in shake flasks at pH 2.0, 180 r·min-1 and 30°C for mesophilic bacteria. The conductivity of copper bioleaching liquid was determined by the electric conductivity method at temperatures ranging from 298 K to 313 K. The ionic activity coefficients were estimated using Debye-Hücker and Osager-Falkenlagen equations. Meanwhile, the effects of temperature and concentration on the mean ionic activity co efficients were discussed. The relative partial molar free energies, enthalpies and entropies of copper leaching solution at above experimental temperatures were calculated The behaviors of change of relative partial molar quantities were dis cussed on the basis of electrolytic solution theory. Simultaneously, the thermodynamic characters of bioleaching solution with and without mesophilic bacteria were compared. The existence of mesophilic bacteria changed the Fe3 /Fe2 ratio, which resulted in the difference of ionic interaction. The experimental data show that the determination of the thermody namic properties during the bioleaching processes should be important 相似文献
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Al-Er和Si-Er二元合金的热力学性质 总被引:2,自引:0,他引:2
以Miedema混合焓模型为基础,计算Al-Er和Si-Er二元合金的部分热力学函数,如混合焓-H,过剩熵SE以及过剩吉布斯自由能GE以及各组元的活度.结合Al-Er和Si-Er二元相图计算了Al3Er和Er5Si3相析出反应的吉布斯自由能.结果表明:Al-Er和Si-Er二元合金的混合焓、过剩自由能与过剩熵在整个浓度范围内均为负值,各组元活度计算结果相对于理想熔体有较大的负偏差,说明Er原子与Al原子和Si原子都有很强的相互作用; Al3Er和Er5Si3相反应的吉布斯自由能均为负值,且Er5Si3相的反应吉布斯自由能比Al3Er相的小,因此Er加入到Al-Si合金中会优先与Si生成Er5Si3相,过剩的Er才与Al生成Al3Er相. 相似文献
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O ver the past decade, the large-scale development and application of magnesium alloys have been greatly stimulated by the demand for lightweight and environment- friendly materials in the automotive industry [1-4]. Most commercial casting magnesium alloys are mainly Mg-Al alloys, such as AZ91D, AM60B, AM50A, AE42, and AS21 alloys. Since AZ91D, AM60B and AM50A alloys contain relatively high Al content they offer a good combination of mechanical properties, corrosion resistance and ca… 相似文献
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测试了热浸镀锌(GI)、锌-5%铝-稀土(GF)和锌-55%铝-1.6%硅(GL)镀层钢板在青岛站的潮差区海水腐蚀行为,并利用腐蚀质量损失测试和显微结构分析,首次研究了3种镀层钢板的海水潮差区腐蚀行为。结果表明:3种镀层在潮差区均出现不同程度的生物污损,与全浸区相比其腐蚀速度明显降低;GI镀层溶解速度最快,氧化膜保护效果不佳,耐腐蚀性能最差;GF镀层的耐蚀性明显提高,潮差区的充气条件又促进了镀层的钝化,表现出较为优异的耐腐蚀性能;由于保护性的锌的腐蚀产物被滞留在富铝的枝晶网络中,比较充分的充气条件又促进了镀层富铝相的钝化,GL镀层在海水潮差区表现出最佳的腐蚀性能。对位于海水潮差区的钢材基体提供1 a保护期所需的镀层最小厚度分别为:GI镀层25μm;GF镀层12μm;GL镀层3μm;GF和GL镀层在潮差区的耐蚀性分别是厚度相当的GI的3倍和5倍。 相似文献
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彩色热镀锌溶液的优化 总被引:2,自引:0,他引:2
在热镀锌溶液中添加Mn,Ti及Ni,Ce,Cu等元素,通过控制镀液温度及冷却条件,直接在钢板上获得了绿色、紫色、蓝色、黄色等色彩,这种多元中获得的彩色镀锌溶液性能优良;采用了百人是方法成功地对彩色镀锌试样的优劣作出了较好的评价。并通过正交试验优化了合金的含量,得到两种最优溶液,即Zn-0.1Mn-0.05Ni-0.01Cu和Zn-0.15Ti-0.1Mn-0.1Ce-0.05Ni-0.01cu。实 相似文献
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热浸镀层在青岛站的海水腐蚀行为对比(Ⅲ)——飞溅区 总被引:1,自引:0,他引:1
测试热浸镀锌(GI)、锌-5%铝-稀土(GF)和锌,55%铝-1.6%硅(GL)镀层钢板在青岛站的飞溅区海水腐蚀行为,并利用腐蚀质量损失测试和显微结构分析,研究3种镀层钢板的海水飞溅区腐蚀行为。结果表明:3种镀层在飞溅区均未发生生物污损,腐蚀速度在3个海水区带中最低;GI镀层由于腐蚀电流密度最大,氧化膜保护效果不佳,耐海水腐蚀性能最差;GF镀层由于腐蚀电流大幅度降低,飞溅区充分的充气条件促进了镀层的钝化,因此表现出较为优异的耐海水腐蚀性能;由于保护性的锌的腐蚀产物被滞留在富铝的枝晶网络中,充分的充气条件又促进了镀层富铝相的钝化,所以GL镀层在海水飞溅区表现出最佳的腐蚀性能。对位于海水飞溅区的钢材基体提供la保护期所需的镀层最小厚度分别为:GI镀层14μm;GF镀层8μm;GL镀层4μm;GF和GL镀层在飞溅区的耐蚀性分别是厚度相当的GI的2倍和4倍。 相似文献
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ZHANG ManMetallurgical Engineering School University of Science Technology Beijing Beijing China 《稀有金属(英文版)》2003,22(1)
After the investigation on the thermodynamic properties and mixing thermodynamic parameters of binary homogeneous metallic melts involving compound, peritectic as well as solid solution, it was found that the equations of mixing free energy △Gm and excess free energy △Cxs of them can be expressed by the following equations: and △GxS =△Gm -RT(alna + blnb), respectively. 相似文献