应用激光熔覆技术提高核阀零件质量

选用5kW横流激光器在核阀阀瓣密封面奥氏体基体上熔覆Co基自熔合金,采用预置粉末法进行激光熔覆改性研究。与常规等离子喷焊层(电弧堆焊层)对比,结果表明:核阀阀瓣密封面经激光熔覆处理后,能获得厚度达3.0mm、表面光滑平整无裂纹的合金层,组织和性能均明显优于喷焊和堆焊工艺。     

阀门密封面用国产铁基合金粉末的性能试验

本文通过对十种国产铁基合金粉末的化学成分、物理性能和各项工艺性能试验,选择了综合性能较好的几个品种作为阀门密封面使用的定型粉末,试验同时表明,国产铁基合金粉末的各项性能已超过2Cr13的水平, 可以在生产中用铁基合金粉末等离子喷焊代替2Cr13手工电弧堆焊密封面。图8。表13。参考文献4。     

激光熔覆阀门零件的研究与应用

使用５ｋＷ横流ＣＯ２激光器对石化系统高参数阀门的密封面进行激光熔覆强化,得到了１ｍｍ￣３．５ｍｍ厚,表面光滑平整的合金层。检测分析表明,激光熔层的组织性能,与基体的结合、对基体的热影响,熔层质量与成品率均优于等离子喷焊等传统强化工艺。     

通用阀门密封面喷焊材料及密封副的研究

应用于工业生产条件下的等离子喷焊通用阀门密封面大部分需采取预热、缓冷等工艺措施。Ｐｅ３０合金粉末不需预热焊，各项性能均达到阀门使用性能要求，经与Ｆ３２６配成密封副，其耐擦伤寿命达国内最好水平，并解决了较大口径阀门冷焊问题。     

铁基合金粉末WF-311喷焊层的相结构分析

在阀门密封面上使用铁基合金粉末WF-311和WF-312等离子喷焊,使焊层金属获得了良好的综合性能,特别是耐磨擦磨损和中温(500℃以下)的硬度稳定性远远地超过了2Cr-13焊条手工堆焊,从而提高了阀门密封面的质量,延长了阀门的使用寿命。为了进一步解释铁基合金粉末焊层金属的良好综合性能,本文对WF-311焊层金属的金相组织及相结构进行了分析。     

阀门、气门密封面表面合金化复合强化技术研究开发及应用示范

该项成果属于“九五”国家重点科技攻关成果。激光熔覆与等离子喷焊和火焰喷焊相比、具有更高的能量密度，就获得更致密、更细小的熔覆质量，是一种能进一步提高阀门、气门等工件表面质量的先进制造技术。该项成果针对阀门密封面以及汽车气门等多种零件采用激光进行表面合金化复合强化技术及装备的研究。主要成果有：1.在武汉材料保护研究所建成激光加工中心及具有年处理30万支汽车和摩托车气门密封面激光熔覆生产示范线。激光发生器选用了5kWCO2横流激光发生器。2.研制成功三类共四种牌号的激光熔覆专用合金粉末。即：用于高温、高压服役…     

D547Mo焊条在深孔堆焊中裂纹的控制

D547Mo焊条是一种优质的高温高压阀门密封面堆焊焊条,在600℃以下可以替代钴基合金焊条,但在深孔密封面堆焊中易产生裂纹。本文通过对其堆焊工艺的研究,提出了解决这一问题的方法,取得了理想的效果。     

应用合金粉末喷熔技术焊补灰铁件

合金粉末喷熔技术是灰铁件焊补的一项新工艺。通过我厂一年多的实践应用,采用这一技术已取得了十分可观的经济效益。现将基本工艺介绍如下。一、对合金粉末的要求合金粉末喷熔技术是利用氧-乙炔焰将具有特殊性能的合金粉末,经过特制的喷焊枪,在1100℃左右高温下,喷熔于铸件表面或缺陷部位,从而使已报废的铸件得到修复。作为灰铁件喷焊补用的合金粉末,最主要的要求是应具有与本体接近的硬度和焊接强度。我们曾选用江苏泰兴合金粉末厂生     

阀门用钴基合金及堆焊工艺

介绍了钴的发现和发展过程，阐述了钴基合金的种类、特性及在阀门产品中的应用．给出了阀门密封面堆焊钴基合金的材料标准及典型工艺方法，对国内高温高压阀门密封面用钴基合金代用材料的研究作了简单的介绍。     

阀门密封面粉末等离子堆焊钴基合金技术研究

阀门密封面采用粉末等离子堆焊工艺(等离子喷焊工艺、PTA焊)自动堆焊钴基合金,较手工堆焊有突出的优越性。阐述了堆焊使用的全数字化控制的新型设备的机型结构及配置,可供选择的钴基合金粉末成分及特性,堆焊工艺稳定性的因素,工艺参数的设定及质量控制要点等。针对阀门密封面堆焊钴基合金的应用,介绍所使用的设备、材料和采用的工艺。     

Application of cold spraying for flux-free brazing of aluminium alloy 6060

In the present study, samples of aluminium alloy 6060 were coated by cold spraying with a powder of brazing alloy Al12Si. The influence of the process gas temperature on particle velocities and coating build-up was investigated. The coated samples were heat-treated in air and under argon atmosphere to investigate the wetting behaviour of the deposited Al12Si and the diffusion processes between Al12Si coatings and substrates. Coated samples were brazed flux-free under argon atmosphere by an induction heating system. The microstructure of the coated, heat-treated, and brazed samples was investigated. The shear strength of the brazed joints was determined. The results show that the brazing alloy Al12Si could be very well deposited on the substrate by cold spraying. The particle velocity increased with increasing process temperature. Correspondingly, the thickness of Al12Si coatings increased with increasing process temperature. The heat treatments showed that a very good metallurgical bond between the Al12Si coatings and the substrate could be realized by the deposition using cold spraying. The coated samples could be well brazed without fluxes. The coating thickness and overlap width influenced the shear strength of the brazed joints. The highest shear strength of brazed joints amounts to 80 MPa.     

Application of cold spraying for flux-free brazing of aluminium alloy 6060

In the present study, samples of aluminium alloy 6060 were coated by cold spraying with a powder of brazing alloy Al12Si. The influence of the process gas temperature on particle velocities and coating build-up was investigated. The coated samples were heat-treated in air and under argon atmosphere to investigate the wetting behaviour of the deposited Al12Si and the diffusion processes between Al12Si coatings and substrates. Coated samples were brazed flux-free under argon atmosphere by an induction heating system. The microstructure of the coated, heat-treated, and brazed samples was investigated. The shear strength of the brazed joints was determined. The results show that the brazing alloy Al12Si could be very well deposited on the substrate by cold spraying. The particle velocity increased with increasing process temperature. Correspondingly, the thickness of Al12Si coatings increased with increasing process temperature. The heat treatments showed that a very good metallurgical bond between the Al12Si coatings and the substrate could be realized by the deposition using cold spraying. The coated samples could be well brazed without fluxes. The coating thickness and overlap width influenced the shear strength of the brazed joints. The highest shear strength of brazed joints amounts to 80 MPa.     

基于等离子熔射成形技术的快速模具制造

提出利用等离子熔射成形技术快速制造模具，以镍基合金粉末NiO1(Ni-Fe-Cr-B-Si）为熔射材料进行快速制模实验研究，详细介绍了其技术特点及工艺过程，讨论了相关的关键技术问题。     

稀土硅对高炉阀门堆焊合金高温耐磨性能的影响

在焊条药皮中加入不同含量稀土硅的试验结果表明 ,适量的稀土硅可提高堆焊合金组织的高温稳定性 ,回火二次硬化和抗蠕变能力 ,细化晶粒 ,改善塑性和韧性 ,使碳化物在晶界聚集形成耐磨网架 ,提高堆焊合金高温耐磨性能     

Evaluation of tribological behavior of Al-co-cr-fe-ni high entropy alloy using molecular dynamics simulation

High‐entropy alloys have been studied extensively for their excellent properties and performance, including outstanding strength and resistance to oxidation at high temperatures. This study employed molecular dynamics simulation to produce a high‐entropy alloy containing an equal molar ratio of Al, Co, Cr, Fe, and Ni and investigated the tribological behavior of the material using a diamond tool in a vacuum environment. We also simulated a AlCoCrFeNi high‐entropy alloy cooled from a high temperature molten state to 300 K in a high‐speed quenching process to produce an amorphous microstructure. In a simulation of nanoscratching, the cutting force–distance curve of high‐entropy alloys was used to evaluate work hardening and stick–slip. An increase in temperature was shown to reduce the scratching force and scratching resistance. Nanoscratching the high‐entropy alloy at elevated temperatures provided evidence of work hardening; however, the degree of work hardening decreased with an increase in temperature. And it can also be found that when the temperature is higher, the fluctuation of the cutting force curve is greater. SCANNING 34: 325–331, 2012. © 2012 Wiley Periodicals, Inc.     

电站阀门用高合金耐热钢焊接工艺的分析

结合国内外相关标准介绍和分析了高温高压电站阀门用10Cr9Mo1VNbN类高合金耐热钢的铸件毛坯的补焊、阀件结构焊和密封面堆焊的焊接基理和工艺过程。     

渗硼的渗层组织和性能研究

渗硼过程中,随着硼浓度的增加,渗硼层的组织由内向外依次为芯部基体、过渡层和硼化物层.如碳钢的低温硼氮共渗层呈梳齿状,表层由FeB、Fe2B双相组成,内层为Fe2B单相.合金钢低温硼氮共渗层的针状变得平坦,渗层的相组成较为复杂,Cr12钢低温硼氮共渗表层由Fe2B、FeB、Fe4N组成,内层相由FeB、Fe2B、Fe3 (C,B)、(Fe,Cr)2B、Fe4N、Fe3C等组成,过渡区形成Fe3 (C,B)、Fe4N相及Cr的碳化物,有效地强化了对硼化物层的支撑作用.渗硼层具有良好的耐磨性、耐腐蚀性.     

Fe3Al基摩擦材料烧结性能及摩擦学特性初探

用球磨机械合金化工艺制备Fe3Al粉末,采用粉末冶金工艺,选择不同的烧结温度、烧结压力和保温时间,获得Fe3Al基复合材料的最佳烧结工艺条件。对最佳工艺条件获得的材料的物理机械性能、摩擦磨损性能和微观结构进行分析测试,借助磨损表面扫描图像和能谱分析,分析该材料的磨损形式,并探讨该材料在低速低载和高速重载2种工况条件的磨损机制。结果表明:采用烧结温度为1 100℃,烧结压力为10 MPa下保温30 min的工艺条件烧结的材料有较好的机械性能和摩擦磨损性能。其摩擦磨损机制为:低速低载以疲劳磨损和磨粒磨损为主,高速重载以疲劳磨损和磨粒磨损为主,并伴有轻微的黏着磨损形式。     

玻璃器皿冲模表面强化材料的研究

玻璃器皿成型工艺对模具材料性能的要求非常苛刻，目前常见的模具设计在周而复始的急冷、急热工况条件下，很快损坏。为此研制出适合玻璃器皿冲模表面强化的自溶性合金粉末材料，并采用热喷涂热核使模具寿命得到提高。     

锰基高强度高塑性高阻尼形状记忆合金研究

用磁悬浮熔炼、测定试样形状记忆效应（SME）、金相法、DSC、断口SEM和自由震动波衰减曲线等研究了高强度高塑性高阻尼的Mn基形状记忆合金的记忆特性,Cu、Ni、Fe、Cr、Ti、N等合金元素的作用。结果表明,Cu溶入愈多,合金的形状记忆效愈高;适当的时效热处理强化合金,提高SME;含Ti、N元素的合金Mn3有最好的SME,回复率达73％。所研究的合金都有明显的双程形状记忆效应,合金Mn3的双程形状记忆效应达21％,比较少见。淬火状态的合金有高的塑性,延伸率达25％,表示有极高的加工工艺性并有良好的阻尼抗震能力。淬火时效状态的合金有高的强度极限,尤其是高的屈服极限（σs=320—475MPa）,适当的塑性（δ=4．2—5％以上）,预示合金有较高的断裂韧性K1c,断裂前会有明显变形预示,提高构件工作安全性。合金元素还能提高所研究合金的抗氧化和抗腐蚀能力。