P—Si上电沉积非晶Ni—W—P薄膜的耐蚀性研究

对Ｐ－Ｓｉ上电沉积Ｎｉ－Ｗ－Ｐ合金薄膜在３％ＮａＣｌ、０．５ｍｏｌ·ｄｍ＾－３Ｈ２ＳＯ４、１ｍｏｌ·ｄｍ＾－３ＨＣｌ介质中的阳极溶解行为进行了研究,ＸＰＳ分析了钝化膜中各元素的化学价态和存在形式。结果表明,非晶Ｎｉ－Ｗ－Ｐ合金薄膜的耐蚀性远优于晶态Ｎｉ－Ｗ－Ｐ薄膜和非晶Ｎｉ－Ｐ薄膜;高Ｗ含量的非晶Ｎｉ－Ｗ－Ｐ合金薄膜,有较强的耐蚀能力;在ＮａＣｌ介质中非晶Ｎｉ－Ｗ－Ｐ合金形成了由Ｎｉ２Ｏ３、ＮｉＨ     

Cu—Co／Ni合金对渗钨石墨的润湿性研究

本文首先在 １． ３３ × １０－３Ｐａ真空下对石墨表面进行了渗钨处理，并在石墨表面生成 了一层Ｗ＋Ｗ２Ｃ＋ＷＣ 表面膜．然后，用座滴法于１．３３×１０－４Ｐａ真空下测定了Ｃｕ－ Ｃｏ／Ｎｉ合金对不同条件下渗钨石墨的润湿角。实验发现，渗钨处理可以大大改善Ｃｕ－ Ｃｏ／Ｎｉ合金对渗钨石墨表面的润湿性。     

高弹性导电合金Cu—Ni—Sn的研究现状

Ｃｕ－Ｎｉ－Ｓｎ合金是调幅分解强化型合金。本文综述了Ｃｕ－Ｎｉ－Ｓｎ合金的研究现状，对材料的制备，热处理工艺，合金的强化机理，微观结构，性能，及它们在电子工业中的应用作了介绍。     

高弹性导电合金Cu-Ni-Sn的研究现状

Ｃｕ－Ｎｉ－Ｓｎ合金是调幅分解强化型合金。与铍青铜相比，该合金性能优良、价格便宜，因此是一种很有发展前途的铜基弹性材料。本文综述了Ｃｕ－Ｎｉ－Ｓｎ合金的研究现状，对材料的制备、热处理工艺、合金的强化机理、微观结构、性能、及它们在电子工业中的应用作了介绍。     

W,P对Ni基非晶镀层耐蚀性能的影响

电沉积Ｎｉ－Ｐ，Ｎｉ－Ｗ和Ｎｉ－Ｗ－Ｐ非晶态合金镀层的阳极化曲线表明，添加类金属Ｐ使镀层的腐蚀电位向正移动，添加高熔点金属Ｗ使维钝电镀密度降低，此外，对Ｎｉ－Ｗ和Ｎｉ－Ｗ－Ｐ合金镀层进行印化处理，可显著提高镀层在ＮａＣｌ溶液中的耐腐蚀性能。     

铝材化学镀镍—铜—磷合金

研究了铝在以次亚磷酸钠为还原剂，柠檬酸钠为络合剂的碱性槽液内化学镀Ｎｉ－Ｃｕ－Ｐ的工艺。分析了影响镀层成分，共沉积过程及镀层与基体结合强度的因素。本文指出，镀液「Ｎｉ＾２＋」／「Ｃｕ＾２＋」在１．２－２０．０范围变化时，可获得含铜（９５－５１）％（ｗｔ）的Ｎｉ－Ｃｕ－Ｐ合金镀层。     

（Ni—W）—WC复合镀层的研究

研究了Ｎｉ－Ｗ合金镀液中添加ＷＣ微粒制备（Ｎｉ－Ｗ）－ＷＣ复合镀层的电沉积过程，表征镀层的结构２和形貌，测试镀层在碱性溶液中的电催化氢析氧性能，探讨镀层的耐蚀性结果表明：（Ｎｉ－Ｗ）－ＷＣ为晶态复合镀层，析氢析氧性能优越，耐蚀性优良。     

化学镀Ni—Cu—B合金及其性能研究

用化学镀方法首次制备了Ｎｉ－Ｃｕ－Ｂ合金镀层。研究了镀液中不同Ｃｕ＾２＋／Ｎｉ＾２＋摩尔比时镀层的沉积速率、表观形貌、结构、Ｃｕ／Ｎｉ原子百分比率、耐蚀性和浸润性，同时研究了热处理对镀层结构和显微硬度的影响。     

CO2饱和高温弱酸性介质中Ni-Cu-P合金、纯Ni和A3钢的电化学行为

用线性极化法,极化曲线法和失重法研究了化学镀Ｎｉ－Ｃｕ－Ｐ非晶态合金,纯Ｎｉ和Ａ３钢于１４０℃,ｐＨ值５．０、ＣＯ２饱和的２Ｗ（ｗｔ）ＮａＳＯ４溶液中的腐蚀电化学行为,结果表明,在该介质条件下,Ｎｉ－Ｃｕ－Ｐ合金、纯Ｎｉ和Ａ３钢的耐蚀性依次减弱,比值为８１．２：２３．９：１．０。Ｎｉ－Ｃｕ－Ｐ合金于２５０￣５５０ｍＶ（ｖｓ ＯＰ）区间发生钝化;纯Ｎｉ在５０￣１５０ｍＶ和高于４００ｍＶ（ｖｓＯＰ）区     

机械合金化Cu—9Ni—6Sn合金的时效

本文对机械合金化法制备的Ｃｕ－９Ｎｉ－６Ｓｎ合金的时效过程研究后发现，时效时发生调幅分解的临界温度为４００－４５０℃。时效前施加一定冷形变量能够加速合金时效强化过程的进程，而且还提高了时效后硬度值。     

高比重合金显微组织,性能与工艺

阐述了高比重合金的显微组织与性能的关系，着重讨论了Ｗ晶粒大小，Ｗ颗粒连接度。Ｗ相含量，组织均匀性，孔隙大小和孔隙度，界面杂质偏析与第二相析出等对合金性能的影响。通过工艺的改进可以改变显微结构，从而改进合金的性能。     

Developing aluminium–zinc-based a new alloy for tribological applications

In order to develop aluminium–zinc-based a new alloy for tribological applications, six binary Al–Zn and seven ternary Al–25Zn–(1–5)Cu were prepared by permanent mould casting. Their microstructure and mechanical properties were investigated. Dry sliding friction and wear properties of the ternary alloys were investigated using a pin-on-disc machine. Surface and subsurface regions of the wear samples were studied with scanning electron microscopy (SEM). The highest hardness and tensile strength were obtained with the Al–25Zn alloy among the binary ones. The microstructure of this alloy consisted of aluminium-rich α and eutectoid α + η phases. Addition of copper to this alloy resulted in the formation of θ (CuAl₂) phase. The hardness of the ternary alloys increased with increasing copper content. The highest tensile and compressive strengths and wear resistance and the lowest friction coefficient were obtained from the ternary Al–25Zn–3Cu alloy. The dimensional change measured on ageing (stabilization) of this alloy was found to be much lower than that obtained from the copper containing zinc-based alloys. Microstructural changes were observed below the surface of the wear samples of the Al–25Zn–3Cu alloy. These changes were related to the heavy deformation of the surface material due to normal and frictional forces, and smearing and oxidation of wear material. Adhesion was found to be the main wear mechanism for the alloys tested.     

钇基重稀土对NBC合金性能的影响

研究了钇基重稀土对NBC合金性能的影响。结果表明：NBC合金经过微量CU-3型稀土的微合金化处理后，其显微硬度、耐磨性和耐腐蚀性均有不同程度的提高，热膨胀系数有所下降；随着稀土加入量的增加，NBC合金的显微硬度逐渐提高，而其磨损量、平均腐蚀速率和热膨胀系数逐渐降低。     

铁基阻尼材料的发展现状和趋势

铁基阻尼材料是一种具有广阔应用前景的结构-功能一体材料,它具有优良的阻尼性能、综合力学性能和冷热加工性能。本文全面地介绍了铁磁型、孪晶型和复相型三类铁基阻尼材料的阻尼机制、研究和应用现状,并对铁基阻尼材料的发展趋势进行了展望。     

难变形材料热静液挤压复合精密塑性成形工艺

目的 研究热静液挤压及其复合塑性变形工艺在高密度钨合金、钨铜合金、钛基复合材料及镁合金薄壁细管等难变形材料方面的制备。方法 通过对高密度钨合金难变形材料进行热静液挤压及旋转锻造等塑性成形,分析了材料在成形过程中的微观组织及性能变化规律和强化机制,制备出大长径比穿甲弹弹芯材料。在此基础上,将该复合塑性变形技术拓展至两相不互溶材料钨铜合金、钛基复合材料及大长径比镁合金毛细管等难变形材料方面的制备。结果 热静液挤压及其复合塑性变形工艺在粉末冶金难变形材料的致密化方面具有显著优势,获得材料不仅致密度高,而且有效实现了控形控性;对于镁合金薄壁细管成形而言,也可以实现组织与性能的有效调配,同时材料的精度较高。结论 热静液挤压及其复合塑性变形工艺在难变形材料的制备与成形方面具有独特的优势与广阔的应用前景。     

钨基高比重合金的制备研究进展综述

综述了当前国内外钨基高比重合金制备的研究进展,介绍了WHAs制备工艺中存在的问题和当前的研究方向.采用机械合金化制取纳米预合金粉是WHAs制备取得突破性进展的新工艺之一;活化烧结和二步烧结可显著改善其力学性能;纳米粉末烧结技术的关键就是在得到全致密合金的同时,保持材料的纳米结构才能对性能作出很大的贡献.     

Zn-Ni合金电镀的研究进展

综述了Zn-Ni合金电镀的工艺特点、沉积机理、镀层耐蚀性机理等的研究现状,分析了Zn-Ni合金镀液体系特性和钝化特性,提出了Zn-Ni合金电镀今后的研究方向,以期为Zn-Ni合金电镀的研究和生产提供参考.     

Influence of Rare-earth Elements on Mechanical Properties of Palladium

The influence of 0.1-0.6 at.-%RE additions (RE= La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Er, Yb) on themechanical properties of Pd was studied. All above RE additions increased not only the strengthproperties at ambient temperature but also the tensile strength, creep rupture time and activation en-ergy at high temperatures, simultaneously increased the elongation of Pd. In the range of dilute con-centration, the strength properties of Pd-RE alloy enhanced linearly with RE concentration. Whenthe strength properties of Pd-RE alloys were normalized at 0.1 at.-%RE, it was found that light REelements had stronger effect on the properties of Pd than heavy RE, whereas Eu, Yb, Ce had anoma-lous effect. In all Pd-RF alloys, Pd-Eu alloy had the highest strength properties, successively Pd-Yband Pd-Ce alloy. The effect mechanisms of RE in alloy, such as purifying impurities, increasingrecrystallization temperature, refining grain size. expanding crystal lattice, increasing dislocation den-sity and decreasing stacking fault energy, forming stable RE oxidation by internal oxidation, and soon, were observed. They were strengthening sensitive factors. The influence of the factors onstrength properties and elongation of Pd was discussed.     

Hypervelocity impact into a high strength and ductile steel alloy

The unusual properties of nitrogen alloyed austenitic steels have been reported in the recent two decades in many papers. In this work it is aimed to investigate a P900 alloy subjected to a hypervelocity impact. The P900 alloy was work hardened to a medium hardness of 380 HV30 by cold expansion of a ring. Tungsten heavy metal and pure tungsten were used as projectile materials. The geometry of the long rods was 3 mm × 30 mm for diameter and length, respectively. Ballistic tests were performed with a two-stage light-gas gun at velocities from about 2000 m/s up to about 4500 m/s. It was found that two kinds of crater geometry are possible depending on the tendency of the projectile material to adiabatic shear banding or brittle fracture. The brittle W material achieved a deeper crater than the shear band forming W heavy alloy.     

Structural modification of Al-Si eutectic alloy by Sr and its effect on tensile and fracture characteristics

Modification of the commercial A-S13 alloy and high purity Al-Si eutectic alloy has been successfully achieved using Al-5 Sr master alloy. The refined structure showed more fine and uniformly distributed eutectic silicon in the high purity alloy. The incidence of Al-dendrites due to modification was related to the movement of the eutectic point to the higher-silicon side. The chill-cast alloys showed better refined structure and higher mechanical properties in comparison with the sand-cast alloys. The modified chill-cast alloy exhibited the best mechanical properties. The ultimate. tensile strength of which reached 280 M Pa and the elongation was 9.2%. The fracture patterns changed from well faceted brittle appearance to smooth silky and dimple-like for the normal and modified alloys respectively. This reflects the change from brittle to ductile behaviour after modification. A model for the fracture mechanism was proposed to explain the observed higher ductility for the modified alloy.