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RE-N-C-S-V-Nb 多元共渗 H13 钢的高温耐磨性 总被引:2,自引:2,他引:0
目的研究RE-N-C-S-V-Nb多元共渗H13钢的高温耐磨性,为避免铝型材挤压模具的早期磨损失效提供表面强化的新工艺。方法把多元共渗试样及对比试样进行高温摩擦磨损实验,然后利用金相显微镜、扫描电镜、能谱分析仪、X射线衍射仪等设备进行检测分析。结果淬火试样和软氮化试样均存在较严重的磨粒磨损和粘着磨损现象,渗层有微裂纹,高温摩擦系数曲线有明显的波动和峰值,磨损率分别为21.20×10-13,11.30×10-13m3/(N·m),在560℃保温4 h后的显微硬度分别为584,1018HV0.1。RE-N-C-S-V-Nb多元共渗试样以微量氧化磨损和微量粘着磨损形式出现,渗层无裂纹,高温摩擦系数曲线平缓,磨损率仅为2.96×10-13m3/(N·m),显微硬度高达1334HV0.1。结论 RE-N-C-S-V-Nb多元共渗H13钢具有较强的高温耐磨性。 相似文献
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采用脉冲电流对退火态和回火态H13热作模具钢进行了改性处理,研究热作模具钢组织、物相、力学性能和热疲劳性能的变化。结果表明,回火态H13钢的强度和硬度高于退火态,回火+脉冲电流处理态H13钢的强度和硬度也高于退火+脉冲电流处理态的,退火态H13钢的断后伸长率要高于回火态H13钢的;经过脉冲电流处理后,H13钢的疲劳裂纹数量减少;随疲劳循环次数增加,H13钢的最长疲劳裂纹长度逐渐增加;在相同的疲劳循环次数下,不同处理状态H13热作模具钢的最长疲劳裂纹长度由长至短依次为退火态、退火+脉冲电流态、回火态以及回火+脉冲电流态;脉冲电流处理可以提高H13热作模具钢的抗热疲劳能力。 相似文献
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用表面机械磨损处理(SMAT)在AISI H13钢上制备一层纳米结构的表面层。研究了这种SMAT试样的渗硼性能和粗晶粒对应物的比较。SMAT试样的硼扩散深度在600℃,2 h渗硼后的峰值是8μm,比粗晶粒试样深得多。在SMAT试样上用600℃接着更高温度的双重渗硼处理能合成厚得多的渗硼层。而且SMAT试样的活化能是1403 kJ/mol,比粗晶粒的209.4 kJ/mol低得多。结果表明,用双重渗硼处理的SMAT试样能明显增强渗硼动力学。而且热疲劳试验表明,具有优良抗氧化性和高温机械强度的渗硼层能有效延迟热疲劳裂纹的萌生,阻碍它们的传播。所以经双重渗硼处理的H13钢的热疲劳性能可以大大提升。 相似文献
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Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems. 相似文献
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The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries. 相似文献
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《中国铸造》2014,(6):537-538
The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less. 相似文献
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《机床与液压》2014,(12)
正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city. 相似文献
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《中国有色金属学会会刊》2014,(6)
正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis 相似文献
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<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of 相似文献
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《中国有色金属学会会刊》2014,(9):F0003-F0003
The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST. 相似文献
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The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward. 相似文献
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《金属学报(英文版)》2014,(5)
<正>Five reviewers and 9 published articles are selected as the Excellent Rewewerand Excellent Article in 2013 respectively.Excellent Reviewers:Prof.Z ongyi Ma(Institute of Metal Research,CAS,C hina);Prof.Y ongbo Xu(Institute of Metal Research,CAS,C hina);Prof.Guangping Zhang(Institute of Metal Research,C AS,C hina);Prof.Z hendui Cui(Tianjin University,China); 相似文献