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在金刚石工具中添加铜磷预合金粉,热压烧结过程中铜磷预合金粉瞬时液化对铁铜基础粉形成钎焊连接,烧结体的致密度、硬度、强度均得到提高。铜磷预合金粉改善单质铁粉和铜粉的润湿性和结合力,并在晶界处生成脆性化合物,增加烧结体的脆性,提高了金刚石工具的锋利度,在金刚石工具行业中具有广阔的应用前景。 相似文献
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《中国有色金属学会会刊》2016,(10)
采用超高压水雾化工艺制备金刚石工具用铜基、铁基、钴基预合金粉末,并对超高压水雾化法、常规水雾化法以及单质金属机械混合粉末制备的金刚石工具烧结节块的力学性能、胎体对金刚石的把持力、空白与含金刚石胎体烧结节块的断口形貌进行测定、比较与分析。结果表明:超高压水雾化预合金粉末烧结节块的相对密度、硬度和抗弯强度等力学性能有显著提高。超高压水雾化预合金粉末烧结节块断口形貌为韧性断裂,预合金粉末与金刚石之间除具有机械嵌镶力外,还存在化学结合力,胎体粉末材料对金刚石的把持能力明显增强。采用超高压水雾化预合金粉末可大大改善金刚石制品胎体的力学性能与使用寿命。 相似文献
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预合金粉末在金刚石工具中的应用 总被引:1,自引:0,他引:1
本文简要综述了超细预合金粉末的特性及其制备方法。重点介绍了超细预合金粉末在金刚石工具中的应用现状。指出在金刚石工具中使用超细预合金粉末具有烧结温度低、烧结温度范围广,对金刚石把持力高等优点。分析了超细预合金粉末在金刚石工具中的应用前景。 相似文献
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进一步提高我国金刚石工具质量的有效途径 总被引:8,自引:5,他引:3
根据我们的实践与调研,就进一步提高我国金刚石工具质量的有效途径进行了探讨。我国金刚石工业必须并可能为金刚石工具制品提供性能稳定、粗颗粒、热稳定性好的高强金刚石。为提高金刚石把持力,有必要在粘结剂中采用强碳化物形成元素或镀覆金刚石,胎体用粉末宜使用超细粉末与预合金化粉末,以便改进胎体性能。在刀头生产中推广制粒工艺,以优化金刚石分布,提高冷压工艺的性能和效率,降低模具消耗。烧结工艺中采用保护气氛热压烧结工艺与设备,在绳锯串珠生产中采用热等静压(HIP)与高温钎焊工艺。激光据片生产中完善刀头烧结工艺与焊接工艺参数,生产高质量的激光据片。 相似文献
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热压富铁基金刚石钻头具有成本低、钻速高的优点,已在钻探中广泛应用。对比相同的热压富铁基胎体配方,通过测试试样的致密度、显微硬度、抗弯强度和抗冲击韧性,研究CSB-2预合金粉质量分数和烧结温度对金刚石钻头胎体力学性能的影响。试验结果表明:添加CSB-2预合金粉的胎体性能均比单质混粉胎体性能好。随CSB-2质量分数的增加,胎体的致密度、显微硬度、抗弯强度和抗冲击韧性分别最大提高了7.68%、27.99%、94.43%和312.82%;同时,胎体粉末预合金化有利于降低胎体的热压烧结温度;为获得良好的应用效果,CSB-2质量分数应大于30%,且最佳烧结温度为940~980℃。 相似文献
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《中国有色金属学报》2019,(6)
通过多金属电解法制备FeNiCo预合金粉末,采用X射线衍射仪和扫描电子显微镜对预合金粉末及其烧结体进行形貌观察和物相分析,研究FeNiCo预合金粉不同温度烧结时烧结体的力学性能和磨损性能,并探讨其在金刚石绳锯中应用的可行性。结果表明:制备的FeNiCo预合金粉一定程度上实现合金化,粉末呈不规则状,粒度较细;FeNiCo预合金粉在800~840℃烧结时,烧结体硬度最大值为107.6 HRB,三点抗弯强度最大值为1638.3MPa,致密度最大值为96.2%,磨损质量损失为0.498~0.555g,烧结温度适应性较好。采用FeNiCo预合金粉为主要胎体成分制作金刚石绳锯锯切硬质石材时,切割效率为8.6 m~2/h,工具寿命为11.3 m~2/m,具有较好的综合使用性能。 相似文献
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使用添加了合金粉A的Ni-Cr合金钎料制备金刚石表面钎焊金属化的磨粒,采用粉末冶金烧结技术制作了多层钎焊金刚石锯片、镀钛金刚石锯片和无镀覆金刚石锯片,并进行了对比切割试验。应用扫描电镜对表面钎焊金属化的金刚石磨粒界面及多层钎焊刀头断面进行了综合分析。结果表明:添加合金粉A既能保证Ni-Cr合金对金刚石磨粒的润湿,又能有效降低钎料对金刚石的损伤;多层钎焊锯片胎体与金刚石磨粒之间出现Ni元素的迁移现象,胎体与金刚石磨粒钎焊层形成了冶金结合;多层钎焊锯片比镀钛锯片具有更高的磨粒把持强度。 相似文献
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V. S. Ivanova 《Metal Science and Heat Treatment》2005,47(7-8):305-311
A synergetic approach to solution of problems of self-controlled synthesis of nanostructures and creation of self-organizing
nanotechnologies is considered in connection with the superproblem of creation of materials with functional properties resembling
those of biosystems.
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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 55 – 61, July, 2005. 相似文献
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C. Colinet 《Intermetallics》2003,11(11-12):1095
A large number of ab-initio calculations of energies of formation of intermetallic compounds have been performed in the last 15 years. The currently used methods are listed. The paper presents a review of the aluminium based compounds which have been studied. Comparisons of calculated and experimental enthalpies of formation are provided for aluminim-3d and-4d transition metal alloys at equiatomic composition. The modelling of the enthalpies of mixing of solid solutions based on a given lattice is described. 相似文献
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O. N. Vlasova N. N. Korneeva V. I. Eremenko O. Kh. Fatkullin N. M. Semenova S. N. Petrova D. D. Vaulin 《Metal Science and Heat Treatment》1991,33(12):924-931
Conclusions To provide a high level of mechanical properties in wrought blanks of cast ÉP741NP and ÉP962 alloys it is necessary to form controlled structures. A necklace-type structure formed in homogenizing isostatic treatment, subsequent thermomechanical working including alternation of the operations of deformation in the (+)-area and recrystallization anneals, and final heat treatment is preferable. The temperature conditions of all stages of thermomechanical working are strictly controlled, especially the final operation of deformation and heating for hardening. To eliminate hardening cracks and distortions it is necessary to use molten salts at t=600°C as quenchants. The use of multiple production operations makes it possible to significantly reduce the structural inhomogeneity related to inhertance of the original dendritic structure. However, the structure of the final semifinished product is nevertheless characterized by a difference in occurrence of the processes of polygonization and recrystallization between the former dendritic cells and the interdendritic spaces in deformation and heat treatment.To obtain structurally homogeneous blanks for gas turbine engine parts it is necessary to use basically new methods of remelting such as vacuum double electrode remelting and electron beam remelting with an intermediate vessel.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 25–29, December, 1991. 相似文献
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The importance of the self-diffusion of a metal during its oxidation by a gas is treated for the cases of nonstoichiometric oxides having either interstitial cation or cation vacancies. We have established a general relationship for the reaction rate when a mixed diffusion process occurs. From this relationship, we have shown that the pressure dependence can be different, according to whether the rate-determining process is the self-diffusion through the metal or through the product. 相似文献
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洋务派在洋务学堂的办学活动中,为了解决西学专业学科的教学困难,采用了聘请外籍教师的应急措施.他们以真才实学,合同制管理作为主导思想,并认为这种解决师资的途径只是权宜之计,并非久远.从客观上看,洋务派的教师聘任思想有深刻的历史影响. 相似文献
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采用激光辐照对FeCrAlW电弧喷涂层的组织进行致密化处理,借助扫描电镜和X衍射对涂层的组织进行了分析.测试了涂层的显微硬度.结果表明:涂层组织致密度提高,孔隙率明显降低.随着激光扫描速度的增加,涂层的显微硬度降低.在较低的扫描速度下,涂层与基体之间形成互熔区,涂层与基体之间产生良好的冶金结合. 相似文献
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论述了CAD技术中参数化设计的三种建模方法,重点介绍了基于特征的参数化建模原理。在此基础上,分析机械设计中的机构结构,归纳出其零件的几何特征构成。设计了机构CAD图形库,并提出了该图形库生成步骤和人机交互界面。 相似文献