铜铬合金的研制

对高导电铜—铬合金的熔炼、热处理进行了测试,并对其铸造性能等进行了测试,提出了铜铬合金铸造工艺要点;用该合金生产的电弧炉电极把持器装机运行表明,该合金是电工行业用的优质导电材料。     

三种高钢级油井管温矫温度特性的研究

对三种高钢级油井管（C90、G105、P110）的应力松弛特性进行了研究,并测量了这些材料制造的无缝钢管经不同温度温矫后残余应力的变化。结果表明,钢材的化学成分对其应力松弛特性有明显的影响,含碳量低及合金元素铬、钼高的C90钢中的残余应力不易消除,而P110的应力稳定性最低。所以在制订钢管的温矫工艺时,材料的化学成分是不容忽视的因素。     

三种高钢级油井管油矫温度特性的研究

对三种高级钢油井管（Ｃ９０，Ｃ１０５，Ｐ１１０）的应力松弛特性进行了研究，并测量了这些材料制造的无缝钢管经不同温度温矫后残余庆力的变化。结果表明，钢材的化学成分对其应力松弛特性有明显的影响，含碳量低及合金元素铬、钼高的Ｃ９０钢中的残余应力不易消除，而Ｐ１１０的应力稳定性最低。所以在制订钢管的温矫工艺时，材料的化学成分是不容忽视的因素。     

高能球磨制备Cu-15wt%Cr合金及其微观组织与性能的研究

本文首先采用高能球磨工艺合成Cu-15wt%Cr预合金粉末,然后热压成形制备铜铬合金.研究了球磨过程合金粉末的微观组织、成形后块体的力学性能和电学性能,探讨了材料的强化机理,揭示了保温时间和热压温度对材料组织性能的影响规律.结果表明,Cu-15wt%Cr可以通过高能球磨工艺形成过饱和固溶体,热压成形后,材料组织细小均匀,兼有细晶强化、弥散强化和析出强化效果,具有优良的综合性能.在900℃热压、保温40分钟,导电性为60%IACS,抗拉强度和硬度分别达到1057MPa和174.8HV.     

薄壁缸体铸件中合金元素的选择

针对柴油机薄壁缸体铸件,试验了少量合金元素铬、铜、锑和锡对高碳当量灰铸铁抗拉强度、硬度及白口倾向的影响,结果表明：合金元素铜对灰铸铁的强度有明显的影响,在碳当量为３．８％￣４．１％的条件下,铁液中合金元素铬、铜和锑的合理含量（％）分别为：０．２０￣０．２５、０．４０￣０．４５以及０．０２。试验条件下,合金元素锡的作用不太明显。初步分析了合金元素铬和铜对灰铸铁强度及组织的影响机理,此外,还进行了实际     

中国机械工程学会焊接学会第四届学术会议论文文摘选登 (二)

大马力柴油机气阀等离子粉末堆焊柴油机车进气阀工作温度在300℃以下,排气阀工作温度为600℃左右。在高温下气阀阀面应有一定的强度、硬度和高的抗氧化、耐腐蚀能力,必须堆焊耐磨合金。本文介绍了气阀等离子粉末堆焊工艺,设备和材料:①等离子弧阀环堆焊和粉末堆焊工艺的比较:粉末堆焊的熔深浅而均匀,焊层稀释小,操作简便,质量稳定;②等离子弧粉末堆焊设备的控制系统和各种形式送粉器的性能对比:认为刮板式送粉器结构紧凑、工作稳定,精度可达到±0.5克/分以下;③堆焊工艺参数的选择;④堆焊合金粉末:除常用的钴铬钨合金粉末外,还试验使用了含铁钴铬钨粉,后者     

铝热还原法制备铜铬合金的研究进展

Cu-Cr合金触头材料具有良好的力学和电学性能,广泛应用于真空开关。本文综述了铝热还原法制备铜铬合金的研究进展,主要包括:铝热还原-电磁铸造法、铝热还原-自耗电弧重熔法及铝热还原-熔渣精炼法。并简要讨论了铝热还原-熔渣精炼法的优化参数。     

高强高导电铜铬稀土合金的研究

采用快速凝固、复合包套成形和挤压等现代粉末冶金技术,系统地制备了铜铬稀土电工材料。通过对材料硬度、软化温度等技术指标的分析测试,筛选出铜铬钇、铜铬镧二种综合性能优异的合金。并利用金相、电镜、差热分析、X射线衍射、物理机械性能和电性能测试等手段,深入地研究了过渡族金属铬和稀土元素（Y、La）对材料的组织结构、再结晶温度、室温高温强度、蠕变断裂强度、电阻率和接触电阻等性能的影响,并且与现行的铜铬合金和弥散强化铜（CuAl2O3）进行了性能比较。研究结果说明,由于采用了粉末冶金新工艺和选择合适的稀土元素作为添加剂,有效地形成了细晶粒晶界强化、第二相弥散强化的组合强化机制;另外,合金形成Cu／CuCrY、Cu／CuCrLa复合表面层,在主体主体料材热稳定性和热强性提高的同时,又保证了材料具有较高的导电性和导热性。成为抗拉强度≥500MPa,硬度（HV）≥120,导电率≥90％IACS,软化温度≥800℃的新型电工材料。为开发高强高导电新材料和对传统电工材料的改性研究,开辟了新途径。通过与现行铜铬和弥散强化铜合金的关键性能比较,其室温高温强度较高,导电率仍然保持在90％IACS以上,达到或超过ISO5182-91和JB4281-86标准。铜铬钇和铜铬镧两种新材料已成功地在汽车行业获得推广     

高能球磨制备Cu-15wt％Cr合金及其微观组织与性能的研究

本文首先采用高能球磨工艺合成Cu15wt％Cr预合金粉末，然后热压成形制备铜铬合金。研究了球磨过程合金粉末的微观组织、成形后块体的力学性能和电学性能，探讨了材料的强化机理，揭示了保温时间和热压温度对材料组织性能的影响规律。结果表明，Cu15wt％Cr可以通过高能球磨工艺形成过饱和固溶体，热压成形后，材料组织细小均匀，兼有细晶强化、弥散强化和析出强化效果，具有优良的综合性能。在900℃热压、保温40分钟，导电性为60％IACS，抗拉强度和硬度分别达到1057MPa和174．8HV。     

纳米级锫基非蒸散型吸气材料制备工艺

一种纳米级锫基非蒸散型吸气材料制备工艺，该制备工艺包括下述步骤：（1）利用物理纳米材料制备方法，将常规锫或锫合金粉末进行颗粒细化，获得颗粒度小于100nm的金属粉末；（2）将细化后的纳米粉末与活性金属间化合物粉末。     

Effect of Fe on microstructures and vacuum arc characteristics of CuCr alloys

In order to clarify the effect of Fe addition on vacuum arc characteristics of CuCr alloys, the CuCr50, CuCr45Fe5 and CuCr40Fe10 alloys were prepared by vacuum sintering and infiltrating, and the simulated electrical breakdown experiment was undertaken in a vacuum interrupter. The characteristics of the motion of vacuum arcs were analyzed by a digital high-speed video camera and the erosion morphology was characterized by a scanning electron microscope (SEM). The results show that Fe additions can strengthen the Cr phase, promote the first breakdown phase to transfer from Cr to Cu and increase the strength of the alloy breakdown voltage by 80%. Meanwhile, Fe additions can still retain the arc stability of CuCr50 alloys during the generation and extinguishing process, decrease the chopping current, and prolong the arc life. Furthermore, the characteristics of the split and motion of cathode spots on the surface of the CuCr40Fe10 alloy were improved, which prohibits the concentrated arc erosion.     

Influence of alloy ingredients on mechanical properties of ternary boride hard alloy clad materials

Using Mo, B-Fe alloy and Fe powders as raw materials, and adding C, Cr and Ni ingredients, respectively, or C, Cr and Ni mixed powders, ternary boride hard alloy clad materials was prepared on Q235 steel substrate by means of in-situ reaction and vacuum liquid phase sintering technology. The influence of alloy ingredients on the mechanical properties of ternary boride hard alloy clad materials was investigated. The results indicate that a mixture of 0.8% C, 5% Cr and 2% Ni ingredients gives a ternary boride hard alloy clad material with optimal mechanical properties, such as high transverse rupture strength, high hardness and good wear resistance.     

Abrasion phenomena of the contact tip in consumable electrode arc welding

ABSTRACT

In GMA welding, presently, fluctuation of the tip of welding wire has been able to restrain precisely, and metal transfer also has been able to regulate periodically, that is stable arc-like TIG welding has been realized. Then at this stage, reduction of contact tip abrasion is the most important subject to maintain arc stability for a long time. In this investigation, many factors are evaluated with abrasion amount, and new material of contact tip is recommended. Results obtained are as follows. Using uncoated welding wire increases contact tip abrasion rapidly as to Cu-coated welding wire. On the contrary, other welding conditions concerning contact point have almost no influence. Under the same current, the abrasion of contact tip is reduced accordingly as welding wire feeding rate becomes higher. Therefore, the abrasion is accelerated violently at the time of arc ignition because of heat accumulation at the contact point by wire stopping and high current which is needed for arc ignition. That is the welding wire which is induced to contact point with room temperature has considerable influence to cool the contact point. As a measure to reduce the abrasion at arc ignition, shortening the period of high current is effective. To cool the contact point positively, thermoelectromotive force was applied. Constantan (Cu-455Ni) has low thermoelectromotive force and high melting point than Fe. So, Cu–Ni alloy (Cu-43.3%Ni-0.92%Mn) was selected and examined as the contact tip material. The abrasion of Cu–Ni alloy contact tip becomes less than about two-tenth of the abrasion of Cu–Cr contact tip. As the conclusion, the best mixed measures which are effective to reduce the contact tip abrasion are using Cu-coated welding wire, wire retract type arc ignition and Cu–Ni alloy contact tip.     

Preparation of CuCr25 alloys through vacuum arc-smelting and their properties

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自蔓延熔铸制备CuCr合金的基础研究

提出了将自蔓延高温合成技术与传统冶金手段相结合的SHS－熔铸技术,充分利用自蔓延高温合成的优点,以CuO,Cr2O3和Al为原料,制备CuCr合金触头材料。通过对CuO-Cr2O3-Al反应体系的绝热温度计算及热力学分析,确定该体系自蔓延反应进行的可行性,并对反应后液态金属Cu和金属Cr的冷凝过程进行了初步的分析与计算。结果表明合金在金属模和石墨模中的冷却速度都比较快,且在石墨模中冷却效果更好些。实验证实该工艺可行,并得到了铸态结构的合金体。     

CuCr合金触头材料的研究现状

CuCr合金触头材料具有良好的力学和电学性能,广泛应用于真空开关。本文综述了不同Cr含量对CuCr触头材料开断能力、截流值、耐电压强度和抗熔焊性等性能的影响,并总结了添加其它新组分对其性能的作用。针对目前CuCr合金存在的问题,提出严格控制原材料成分及杂质含量、添加新组分,是目前改善或获得高性能CuCr触头材料的发展方向之一。     

Diamond and graphite coated with polyalloys by an immersion method

A method of coating diamond and graphite with polyalloys, such as Ti–Co–Cu, Cr–Ni–Cu, W–Cu–Co, etc., is presented in this paper. By adding a small amount of Ti powder, CoCl₂ and CuCl into NaCl–KCl molten salt system, and immersing diamond or graphite into it, the reactions which listed thereafter: Ti+CoCl₂→TiCl₂+Co, Ti+CuCl→TiCl₂+Cu, C+TiCl₂→TiCl₄+TiC, etc., occurred, and finally a Ti–Co–Cu coating was deposited on the diamond or graphite surface. Other polyalloy coatings, such as Cr–Ni–Cu, Cr–Co–Cu, and W–Cu–Co, etc., were also deposited in almost the same way. The coated materials were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with a wavelength dispersive spectrometer (WDS) line profile analysis. XRD analysis showed that the carbides of Ti, Cr, or W were formed during the coating process. It was also found that no vacuum or protective atmosphere was needed during the process.     

不同Cr含量CuCr触头材料的组织与性能对比(英文)

为研究Cr含量对CuCr触头材料组织和性能的影响,采用真空熔铸法制备三种(CuCr25、CuCr30、CuCr40)不同Cr含量的触头材料,并对这3种材料的显微组织、物理性能及电流开断性能进行对比研究。结果表明:随着Cr含量的增加,CuCr材料微观组织的致密度提高,Cr颗粒得到细化,但是Cu基体中固溶的Cr含量增加;材料的电导率和密度均降低,硬度增加,抗拉强度呈线性增加;CuCr25和CuCr30的电流开断能力相当,CuCr40较低。     

Cu-Cr触头合金制备技术的发展

通过对近年来Cu-Cr合金制备技术的回顾，综述了Cu-Cr合金制备技术的进展。论述了该合金的化学成分及显微组织对电性能的影响，包括Cr含量的影响、第三组元的影响、合金中杂质的影响、Cr粒子宏观分布的影响、Cr粒子尺寸的影响、合金致密度的影响、热处理工艺的影响以及表面老炼处理的影响。介绍并分析了Cu-Cr合金的几种主要制备工艺，包括粉末烧结法、熔渗法、电弧熔炼法、自耗电极法以及最近发展起来的低偏析熔铸法；最后，对Cu-Cr合金进一步发展方向，如发展熔铸技术、Cr粒子细化、进一步减少Cr含量以及添加第三组元等进行了简要的讨论。     

Surface free energy of copper-zinc alloy for energy-saving of boiler

Cu-Zn, Cu-Zn-Sn, Cu-Zn-Ni alloys were melted by vacuum smelter. The effect factors to the surface free energy of the alloys such as chemical composition, crystal structure and surface crystal lattice distortion etc. were investigated by OCA30 automatic contact angle test instrument, metallography microscope and XRD instrument etc. Results suggests: adding alloy element to Cu may increase its surface free energy, and the more kinds of alloy elements are added, the more surface free energy increases; the alloy element Sn an increase the surface free energy of Cu-Zn alloy; Cu-Zn alloy with fir-tree crystal structure, great phase discrepancy and obvious composition aliquation has greater surface free energy; Cu-Zn alloy with compounds and serious surface crystal lattice distortion has greater surface free energy.