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1.
Zr基大块非晶合金成分的等电子浓度和等原子尺寸判据   总被引:6,自引:0,他引:6  
制备了6种合金Zr65.5Al5.6Ni6.5Cu22.4,Zr65.3Al6.5Ni8.2Cu20,Zr65Al7.5Ni10Cu7.5,Zr64.8Al8.3Ni11.4Cu5.5,Zr64.5Al9.2Ni13.2Cu13.1和Zr63.8Al11.4Ni17.2Cu7.6,共晶成分位于合金Zr64.5Al9.2Ni13.2Cu13.1和合金Zr63.8Al11.4Ni17.2Cu7.6的成分之间,这6种合金均显示了非晶相的形成和较宽的过冷液相区范围△Tx值,以及较大的约化玻璃转变温度Trg值,除合金Zr63.8Al11.4Ni17.2Cu7.6的△Tx值为87K外,其余5种成分合金的△Tx值均在97K以上,最宽的达105K,表明这6种合金是一个具有大玻璃形成能力和高热稳定性的非晶合金系列,合金Zr63.8Al11.4Ni17.2Cu7.6是6种合金中玻璃表成能力和热稳定性最高的,其Tg,Tx和Trg值最高,Inoue非晶合金Zr65Al7.5Ni10Cu17.5并不是最佳非晶成分,提出以等电子浓度和等原子尺寸规律作为设计大块非晶合金成分的判据。  相似文献   

2.
利用铜模铸造方法制备了具有大过冷液相温度区间的Cu-Zr-Ti-Ni系高强度Cu基大块非晶合金,对于Cu55Zr55Ti15Ni5合金,最大直径达5mm.过冷液相区温度范围ΔTx达45.48~70.98 K.Cu基玻璃合金棒表现出非常高的机械性能和明显的塑性,对于Cu50Zr25Ti15Ni10、Cu55Zr25Ti15Ni5和Cu54Zr22Ti18Ni6合金,压缩断裂强度分别达2155MPa、2026MPa和1904MPa,维氏硬度分别达674、678和685.加入Co元素扩大了CuZr-Ti-Ni系合金的ΔTx,Cu50Zr22Ti18Ni6Co4合金的ΔTx高达74.5K.  相似文献   

3.
为了进一步提高铜基大块非晶合金的玻璃形成能力及力学性能,采用添加微量Al元素的方法对块体非晶合金Cu52.5Ti30Zr11.5Ni6进行了成分优化.热分析与X射线衍射结果显示,随着微量Al的添加,液相线温度从非晶合金Cu52.5Ti30Zr11.5Ni6的1150 K逐步降低到Cu50.5Ti30Zr11.5Ni6Al2的1134 K,临界直径相应的从5 mm提高到6 mm.大块非晶Cu50.5Ti30Zr11.5Ni6Al2的压缩断裂强度达到2286 MPa,比经典的铜基非晶合金Cu47Ti34Zr11Ni8提高约100 MPa,表明微量Al的添加在有效提高玻璃形成能力的同时,强度也略有提高.  相似文献   

4.
大块非晶合金又称大块金属玻璃,是一种具有特殊结构与性能的新型金属材料.本文利用同步辐射XRD技术研究了常压和11.6GPa压力下Zr41.2Ti13.8Cu12.5Ni10Be22.5大块非晶合金结构以及0~50GPa压力范围内Fe60Co10Zr8Mo5Nb2B15大块非晶形成合金结构特征的演变.另外,利用同步辐射XRD研究了冲击波处理和水淬条件下制备的Zr41.2Ti13.8Cu12.5Ni10Be22.5大块非晶合金微观原子构型的差异.研究表明,压力与制备条件对大块非晶合金的结构均有一定影响,本研究对深入了解大块非晶合金结构本质及进一步开发该类材料具有重要理论和现实意义.  相似文献   

5.
应用铜模真空吸铸法制备直径达5mm的棒状新型Zr57Nb5Cu154Ni12.6Al10大块非晶样品.X射线衍射检测证明样品完全为非晶态.通过等温示差扫描量热法(DSC)测试了Zr57Nb5Cu15.4Ni12.6Al10大块非晶的晶化动力学效应,同时研究了大块非晶合金的室温单轴压缩变形和断裂行为.结果表明:Zr57Nb5Cu15.4Ni12.6Al10块体非晶晶化过程具有动力学效应;其室温压缩变形过程主要表现为弹性变形;断裂面与压缩方向约呈45°,断口呈现典型的脉状花样.  相似文献   

6.
Cu-Zr-Al-Ti块体非晶合金的制备及腐蚀行为研究   总被引:2,自引:2,他引:0  
制备出新型Cu46 Zr46 Al4 Ti4块体非晶合金.利用X射线衍射仪和差示扫描量热仪对其非晶态进行表征,采用电化学方法和扫描电子显微镜研究了非晶合金在3.5% NaCl溶液中的电化学行为.结果表明,Cu46Zr46-Al4 Ti4样品为完全非晶,玻璃转变温度Tg、晶化温度Tx和过冷液相区△Tx都有所降低,断裂强度提高了约11%.Cu46 Zr46 Al4 Ti4的腐蚀电流密度降低了1个数量级,电化学反应电阻R1大大增加.分析表明,Ti通过抑制阴极过程从而降低了非晶合金的腐蚀速度,其机理可能是Ti的加入降低了活性阴极的面积或增加了氧的离子化过电位.  相似文献   

7.
根据二元共晶混合法设计Zr-Cu-Ni-Al非晶合金成分,利用铜模吸铸法制备Zr-Cu-Ni-Al合金棒材.采用XRD、DSC、SEM及准静态压缩实验研究了所设计合金的非晶形成能力和力学性能.结果表明:所设计的Zr-Cu-Ni-Al合金均为非晶态结构,其过冷液相区(ΔTx)均超过65 K,有较好的非晶形成能力,其中Zr55.7 Cu22.4 Ni7.2 Al14.7合金的ΔTx最宽,达到82 K;合金的塑性变形能力由低到高依次为:Zr57 Cu18.67 Ni8 Al16.33、Zr56.36 Cu20.53-Ni7.6 Al15.51、Zr54.4 Cu26.13 Ni6.4 Al13.07和Zr55.7 Cu22.4 Ni7.2 Al14.7,其中Zr55.7 Cu22.4 Ni7.2 Al14.7的塑性达到5.5%,抗压强度达到1885 MPa,其他三种合金的塑性均不足2%.剪切带的增殖和交互作用与非晶合金的塑性和强度密切相关.合金试样断口中均有熔滴存在,这表明在合金变形过程中,断裂处的合金组织发生了粘性流动,并伴有脉纹产生.合金在塑性变形中均发生了锯齿流变,锯齿流变与自由体积的变化密切相关.  相似文献   

8.
弛豫对Zr-Al-Ni-Cu基非晶合金晶化过程的影响   总被引:1,自引:0,他引:1  
齐民  王晓东 《功能材料》2002,33(2):220-222
非晶合金的稳定性是制备大块非晶合金的关键,而弛豫后形成的短程有序结构对非晶中的晶体相形核有重要的影响。本文通过差热分析及X射线衍射法研究了预先弛豫处理对Zr60Al8Ni12.5Cu17Si2.5和Zr60Al8Ni10Cu17Si5非晶合金晶化过程的影响。结果表明:预先弛豫处理降低了上述非晶合金的稳定性。Si含量的增加则提高上述非晶合金的稳定性。根据等温转变过程日体相形核孕育期采用Arrhenius公式所确定的晶化激活能更能反映非晶晶化过程及非晶的稳定性。  相似文献   

9.
利用CHI660B型电化学工作站研究了4种不同成分(Zr55Al10Ni5Cu30,Zr60Al15Ni25,Zr65Al10Ni10Cu15,Xr52.5Al0Ni10Cu15Be12.5)的锆基非晶态合金以及其中两种成分(Zr65Al10Ni10Cu15,Zr52.5Al10Ni10Cu15Be12.5)的晶态合金在2.5mol/L的HCl溶液中的腐蚀行为。通过Tafel曲线的测试结果表明,非晶合金的耐腐蚀性能与其成分有很大的关系,这4种非晶合金试样的耐腐蚀性由强到弱的顺序依次为Zr60Al15Ni25〉Zr65Al10Ni10CU15〉Zr52.5Al10Ni10Cu15Be12.5〉Zr55Al10Ni5Cu30。两种成分的非晶态合金与其对应成分的晶态试样相比,非晶态合金具有较低的腐蚀电流,显示出较好的耐腐蚀性。最后,根据电化学腐蚀原理,从合金的微观结构、化学成分以及腐蚀介质的性质3个方面探讨了影响合金耐腐蚀性的因素。  相似文献   

10.
用单辊铜轮旋注法制备了TiC颗粒增强Ti45Zr5Cu25Ni20Sn5非晶合金基复合材料.发现在Ti45Zr5Cu25Ni20Sn5非晶合金中加入TiC颗粒可以提高合金的热稳定性.  相似文献   

11.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

12.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

13.
Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.  相似文献   

14.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

15.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

16.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

17.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

18.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

19.
正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from  相似文献   

20.
正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.  相似文献   

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