Co—Cr3C2合金与WC润湿性的观察和分析

采用实况采相观察了Ｃｏ－Ｃｒ３Ｃ２合金与ＷＣ的润湿现象，采用ＪＣＸＡ－７３３型电子探针显微分析仪和３０１４型Ｘ射线衍射仪研究了Ｃｏ－Ｃｒ３Ｃ２合金熔渗ＷＣ所形成的组织，为ＷＣ－Ｃｏ合金中添加Ｃｒ３Ｃ２的作用机理提供解释依据。     

高速钢W6Mo5Cr4V2的脱磷试验

在３０ｋｇ感应炉上用ＣａＯ－Ｎａ２ＣＯ３－ＣａＦ２－ＦｅｘＯ（ＭｏＯ３）渣、ＭｏＣｌ６粉剂和Ａｌ－Ｃａ合金作脱磷剂对高速钢Ｗ６Ｍｏ５Ｃｒ４Ｖ２进行脱磷试验。结果表明，ＣａＯ－Ｎａ２ＣＯ３－ＣａＦ２－ＦｅｘＯ渣的脱磷效果最好，一般脱磷率可达２６％￣５６％。     

铁基高温合金GH2871成分对组织和性能的影响

开发出新型含０．５％Ｎｂ，并以Ｗ、Ｍｏ复合固溶强化的２８Ｎｉ－１４Ｃｒ－１．ＯＷ－１．５Ｍｏ－２．１Ｔｉ－Ｎｂ－Ａｌ铁基高温合金ＧＨ２８７１。该合金的综合机械性能优于同类２５Ｎｉ－１５Ｃｒ铁基高温合金。     

低合金高性能高速钢中的碳化物及其对刀具切削寿命的影响

研究了Ｗ４Ｍｏ３Ｃｒ４ＶＳｉ低合金高性能高速钢的碳化物数量及成分特点，发现此钢的一次碳化物数量明显少于Ｍ２钢，而二次硬化碳化物中铬含量比Ｍ２钢高。文中对比分析了Ｗ４Ｍｏ３Ｃｒ４ＶＳｉ和Ｍ２钢的的二次硬化碳化物析出能力，并根据一次，二次硬化碳化物对高速钢切削寿命的贡献说明了Ｗ４ＭｏＣｒ４ＶＳｉ钢利用合金成分设计，在大大节约贵重合金元素Ｗ，Ｍｏ的条件下获得与通用高速钢相当的切削寿命的原因。     

氩弧熔覆Ni35B+Co-WC层的组织、性能及强化机制

采用氩弧熔覆工艺在Ｑ２３５ 基材上熔覆Ｎｉ３５Ｂ＋ Ｃｏ－ＷＣ,获得了具有较高硬度和耐磨性的熔覆层。分析了熔覆层的显微组织、硬度和耐磨性及物相形貌和相结构等,证明熔覆层的强化机制是：①形成细小的Ｍ６Ｃ型合金化合物网架;②高度弥散的粒状Ｍ６Ｃ型合金化合物颗粒和极细小的Ｃｒ２Ｎｉ３ Ｂ及ＷＣ颗粒的弥散强化;③Ｃ、Ｃｒ及Ｂ等合金元素溶入α－Ｆｅ（Ｍｅ）和γ－Ｎｉ（Ｍｅ）中产生的固溶强化。     

耐蚀合金中钒的直接光度测定

耐蚀合金中钒的直接光度测定梁培德（机械工业部重庆仪表材料研究所,重庆,６３０７００）耐蚀合金多为含钨、钼、铬、钴的镍基或半铁镍基合金。如３ＹＣ２４（ＮｉＭｏ１７Ｃｒ１６Ｗ４）,ＮｉＭｏ２８,０Ｃｒ１５Ｎｉ２６、哈氏Ｂ－２及Ｃ－２７６等均含有少量钒。测...     

新型热作模具钢（JM）的研究与应用

５Ｃｒ４Ｗ４ＭｏＶＮｂ钢（ＪＭ）是一种新型加钒、铌的Ｃｒ－Ｗ－Ｍｏ热作模具钢。应用结果表明，该钢具有良好的锻造性能和机械加工性能，用该钢制作的精锻齿模和扳手模的使用寿命比３Ｃｒ２Ｗ８Ｖ钢提高１倍以上。     

电感耦合高频等离子体法在相分析中的应用

应用电感耦合高频等体光源对Ｗ９Ｍｏ３Ｃｒ４Ｖ高速钢及ＯＯ（ｒ２８Ａｌ２Ｚｒ合金、ＧＨ２１７合金中相组成元素进行光谱分析，同时对酸给予试样的影响及仪器的工作条件等进行了选择。相对标准偏差（％）Ｗ８．２８Ｍｏ１０．０，Ｃｒ８．４２，Ｆｅ１０．１。     

铁基金温合金GH2871成分对组织和性能的影响

开发出新型含０．５％Ｎｂ，并以Ｗ，Ｍｏ复合固溶强化的２８Ｎｉ－１４Ｃｒ－１．０Ｗｏ－２．１Ｔｉ－Ｎｂ－Ａｌ铁基高温合金ＧＨ２８７１。该合金的综合机械性能优于同类２５Ｎｉ－１５Ｃｒ铁基高温合金。     

WC—Co—Ni硬质合金断裂行为的观察与分析

结合ＷＣ－Ｃｏ－ＮＩ硬质合金工业生产中的质量检测工作，采用光学显微镜和ＪＣＸＡ－７３３型电子探针显微分析仪，应用二次电子图像（ＳＥＩ），背散射电子图像，特征Ｘ射线扫描图象，观察和分析了该合金的断裂行为，讨论了降低合金强度的因素。     

Effects of Ni60WC25 powder content on the microstructure and wear properties of WC<Subscript>p</Subscript> reinforced surface metal matrix composites

The vacuum evaporative pattern casting technique was used to fabricate WC_p reinforced surface metal matrix composites in order to study the effects of Ni60WC25 powder content on the microstructure and wear properties of it. The results showed that the Ni60WC25 powders weakened the stability of WC particles and reacted with metal matrix at the interfacial regions in the composite. Diffusion kinetics and Gibbs free energy were calculated from the interactions between WC particles and matrix. It was found that adding 35 vol% Ni60WC25 alloy powder to composites led to the formation of Fe₃W₃C phases and complete dissolution of WC particles. The wear properties of composites with different Ni60WC25 alloy powder content were tested by the MLD-10 type tester. WC particles and Fe₃W₃C phases could protect the matrix and the matrix could support WC particles and Fe₃W₃C phases during wear processing.     

Micro-Crystalline Coatings of Co-Cr Dispersed with Y2O3 Deposited by Series Electro-Pulse Discharge

A new technique-series electro-pulse discharge (SEPD)-was developed as a kind of surface coating process. In this technique, both positive and negative poles of a pulse power were used as the depositing electrodes with the substrate alloy as an induction electrode. Micro-crystalline Co-Cr and Co-Cr dispersed with Y2O3 coatings were deposited on Fe-18Cr-SNi stainless steel surface by using Co30Cr alloy as the depositing electrodes. Oxidation at 950℃ in ambient air shows that these coatings greatly improve the oxidation resistance of the steel. The addition of dispersed Y2O3 nano-particles into the alloy coatings was found to further reduce the scaling rate and enhance the adhesion of oxide scales.     

硬质合金中WC相的塑性变形

用两种不同的原料制造同种牌号的硬质合金，并对其微观组织进行了TEM分析，通过对电子衍射花样的标定，确定了WC相中存在W2C、WC1-x等相。同时对两种合金施加了一定的应变，研究了其滑移、孪生变形特性，结果表明，当WC为单一相时，WC相能产生孪生-滑移协调变形，从而具有较高的塑性。这种高塑性合金，可满足凿岩领域的使用要求。     

预弥散强化镍粉——硬质合金的新型粘结剂

叙述了以预弥散有纳米Ａｌ２Ｏ３的镍粉代替钴粉作粘结剂以提高ＷＣＮｉ硬质合金性能方面的初步研究；制得的ＷＣＮｉ硬质合金的物理机械性能可达到ＷＣＣｏ合金的水平     

WC相的TEM研究

采用不同工艺处理的原材料、不同的烧结处理制度等,将导致合金中WC微观结构的变化,从而不同程度的影响着合金的性能。了解和掌握这些知识对于生产高质量的硬质合金具有重要意义。对自贡硬质合金有限责任公司生产的YG11C合金进行了仔细的TEM研究,了解其WC相的微观结构,结果表明,在WC相中,除了存在WC相外,还存在着W2C、WC(1-X)等相。     

Low Temperature Hot Corrosion of Cobalt-Base Alloys: PartI. Morphology of the Reaction Product

Accelerated oxidation tests have been conducted on a number of Co-Cr, Co-Al, and Co-Cr-Al alloys coated with a thin film of Na₂SO₄ and exposed at 600 to 750 °C in O₂-SO₂-SO₃ environments containing 0.0095-5 pct (SO₂ + SO₃). Generally, Co-Cr and Co-Cr-Al alloys reacted nonuniformly, usually in the form of pits, and Co-Al alloys suffered broad frontal attack. The morphology of the reaction product was observed to be dependent on temperature andP _SO3 Under all conditions, a thin sulfur-rich band containing sulfides was observed at the alloy/scale interface, and cobalt dissolved near this interface and formed Co₃O₄ and/or CoSO₄(s) in different regions of the reaction product.     

Effect of Hot Rolling Practice on Microstructure and Mechanical Properties of Fire-Resistant Steel

Trials to develop a C-Mn-Mo-Nb type fire-resistant steel have been carried out by adopting recrystallization rolling (RCR) + air cooling (AC),two-stage rolling (TSR) + AC and RCR + water cooling (WC).Both RCR and TSR followed by AC resulted in polygonal ferrite (F) + pearlite (P) microstructure,while F + bainite (B) microstructure was formed by RCR + WC.The plates with F+P microstructure show tensile strengths ≥490MPa,while those with F+B exhibit tensile strengths ≥590MPa.All the plates show favorable low yield ratios ≤ 0.75,good charpy v-notch impact property >101J at 0℃ and satisfactory high temperature strength (≥2/3 of room temperature yield strength retained at 600℃).     

高锰钢表面激光熔覆 Fe-WC 复合涂层的组织与性能

采用激光熔覆技术在高锰钢基体上制备了不同WC含量的Fe-WC复合熔覆层,研究了WC添加量对熔覆层组织和性能的影响。试验结果表明,不同WC含量的Fe-WC熔覆层均含有马氏体、M7C3碳化物和未熔WC颗粒,当加入20wt.%的WC时,熔覆层中出现了残余奥氏体,共晶碳化物呈鱼骨状沿晶界析出。Fe-WC熔覆层的硬度和耐磨性随着WC添加量的增多而增大,熔覆层中WC颗粒减小熔覆层基体与对磨副的接触面积,合金基体固定和支撑WC颗粒避免其剥落,二者协同作用使得熔覆层耐磨性增加。     

Compaction features during sintering VN8M alloy with additives of nanodimensional tungsten carbide

Shrinkage curves of alloys formed from the WC–8% Ni hard-alloy mixture activated by introducing 10% nanodimensional WC and charge without the additive in a temperature range of 800–1500°C are presented. The pore structure and microstructure of the samples at various stages of sintering are investigated. The peculiarity of densification of the modified alloy, which consists in the shift of the shrinkage curve into the lower temperature region, is revealed. This makes it possible to lower the temperature of the vacuumcompression sintering of alloy, form a finer grain structure, and attain high characteristics of hardness–wear resistance without worsening the strength characteristics. Physicomechanical properties and microstructure of compression-sintered samples made of VN8M activated alloy and standard VN8 alloy without additives are investigated.     

非均匀WC颗粒对YG20C合金力学性能与组织结构的影响

在WC颗粒平均粒径为25μm的YG20C粗颗粒合金中,加入不同比例的平均粒径为2.0μm的WC,构成非均匀搭配,经湿磨、压制、烧结后测试结果表明,细颗粒碳化钨的加入量在20%时,合金有较高的强度,硬度以及较好的使用效果。