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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.
采用机械合金化法制备了Fe70Zr10B20、Fe63Co7Zr10B20和Fe63Ni7Zr10B20合金.利用X射线衍射仪(XRD)研究了3种合金的机械合金化过程及晶化过程.Fe70Zr10 B20球磨50h后的合金由大量非晶相和少量晶态相组成,Co的添加对FeZrB非晶合金的形成起到了抑制作用;Ni的添加对FeZrB非晶合金的形成起到了促进作用.Fe70-Zr10B20、Fe63Co7Zr10B20合金的晶化过程容易进行,而Fe63 Ni7Zr10 B20合金的晶化比较困难.  相似文献   

3.
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   

4.
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   

5.
Zr-Al-Ni-Cu大块非晶合金的电化学腐蚀行为研究   总被引:1,自引:0,他引:1  
用电化学方法研究了 6种不同成分的大块非晶合金、与非晶成分相对应的两种晶态合金和纯Zr在 0 .1mol/LNa2 SO4 溶液中的腐蚀行为 ,结果表明 ,6种非晶样品中 ,有 4种具有高耐蚀性能 ,其中 ,成分为Zr65Al7.5Ni10 Cu17.5的样品具有最低的icorr值 1.38× 10 - 2 μA·cm- 2 。两种具有相同成分的非晶与晶态合金相比 ,晶态合金具有更低的icorr值。在 9种实验样品中纯Zr具有最低的icorr值 7.10× 10 - 3 μA·cm- 2 。  相似文献   

6.
大块非晶合金的性能、制备及应用   总被引:4,自引:0,他引:4  
综述了大块非晶合金的性能、制备方法及应用,对比了吸铸法制备的棒状Zr41.2Ti13.8Cu12.5Ni10Be22.5,Zr57Cu20Al10Ni8Ti5,Zr52.5Ti5Cu17.9Ni14.6Al10(原子分数)大块非晶样品的过冷温度区间宽度(△Tx),给出了3种大块非晶合金系列的热稳定性参数Tg、Tx及△Tx,提出了大块非晶合金领域存在的问题及发展方向.  相似文献   

7.
Zr对Pr-Fe-B非晶合金晶化形成纳米晶合金的作用   总被引:2,自引:0,他引:2  
从非晶合金化激活能的角度,分析了Pr-Fe-B非晶合金在退火过程中晶粒粗大的原因,揭示了Zr元素在其晶化过程中的作用,结果表明,Zr能改变Pr-Fe-B非晶合金中α-Fe相的晶化行为,有助于形成尺寸细小的α-Fe相。  相似文献   

8.
采用机械合金化法制备Fe88-xZrxB12(X=5、10、15、20)系合金,利用X射线衍射仪(XRD)、差热分析仪(DTA)等测试手段对样品的结构及晶化进行研究.XRD结果表明,球磨60h,Fe88-xZrxB12(x=5、10、15)已形成α-Fe固溶体,Fe68Zr20B12完全形成非晶合金,表明Zr含量的增加使合金的非晶形成能力增强.Fe88-xZrxB12(x=5、10、15、20)合金的DTA图中均出现2个晶化放热峰.Fe68Zr20B12非晶合金的晶化模式为一次晶化.  相似文献   

9.
目的 研究不同的应变速率和变形温度对Zr30.2Ti32.9Cu9Ni5.3Be22.6非晶合金(亦称ZT3)在过冷液相区塑性变形行为的影响。方法 首先,用真空非自耗电弧炉熔炼合金锭并吸铸成直径为8 mm、长度为60~80 mm的非晶合金圆棒;然后,通过等温晶化试验确定ZT3非晶合金在过冷液相区中对应不同温度时发生晶化转变所需的最短时间,并用热模拟试验机进行压缩变形的试验研究;最后,用X射线衍射仪测试ZT3非晶合金在过冷液相区塑性变形后的组织特性。结果 ZT3非晶合金在过冷液相区内的塑形变形行为与应变速率和变形温度有密切的关联性。不同的应变速率与变形温度都会对其塑性变形产生影响,但变形温度的影响比恒定应变速率更大。对ZT3非晶合金变形后的结构分析发现,应变速率对非晶态结构的影响大于温度。结论 ZT3非晶合金的等温晶化转变孕育时间最短为17 min,在小于17 min的时间内完成塑性变形即可抑制晶化转变的发生。当恒定应变速率为2×10?3 s?1时,将变形温度控制在355~375 ℃范围内有利于ZT3非晶合金在过冷液相区进行热压塑性成形。  相似文献   

10.
采用悬浮熔炼-水冷铜模吸铸法制备了(Ti0.5Ni0.5-xZrx)80Cu20(x=0,0.02,0.04,0.06和0.08)。通过对Zr的添加量的控制制备具有组织连续梯度的非晶复合材料,研究其组织和力学行为及微量Zr的添加对此非晶复合材料的组织和力学性能的影响。结果表明,凝固过程的温度梯度决定了复合材料的组织梯度,由表及里,主要为非晶相、马氏体相和奥氏体树枝晶相。铸态非晶基体上析出了B2-Ti(Ni,Cu)过冷奥氏体相和B19’-Ti(Ni,Cu)热诱发马氏体相,加载断裂后应力诱发马氏体相变,马氏体衍射峰比铸态增强且马氏体择优取向。随着Zr的不断添加,此系列非晶合金非晶形成能力先提高后降低,奥氏体含量不断下降,相变诱发塑性减弱,从而塑性逐级递减,强度先升高后降低。  相似文献   

11.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

12.
13.
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   

14.
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   

15.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.  相似文献   

16.
On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……  相似文献   

17.
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   

18.
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill.  相似文献   

19.
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   

20.
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   

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