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1.
WC—Co硬质合金的饱和磁化强度   总被引:1,自引:0,他引:1  
探讨了WC-Co硬质合金饱和磁化强度的影响因素、磁化机制和比饱和磁化强度4πσ与抗弯强度σ(TRS)的关系。结果表明,影响WC-Co合金4πσ的主要因素是γ相含量和γ相成分,其次是γ相结构。其4πσ同合金标称钴含量或合金碳含量间均不存在单一性对应关系。γ相分布和热处理及添加稀土元素对合金4πσ的影响,实质上仍归结为上述基本因素的作用。WC-Co合金的4πσ同抗弯强度间并不存在明确的对应关系,因而难以用饱和磁化强度(Ms或4πσ)取代σ(TRS)的测定。  相似文献   

2.
研究了配碳量与Ni/Co比对WC-9(Ni-Co)硬质合金抗弯强度的影响。实验结果表明:WC-3Ni-6Co的配碳量是6.04wt%时,其抗弯强度与WC-9Co硬质合金相当;Ni的分布均匀性对抗弯强度的影响极其重要,粗粒Ni粉或(和)较多η相的存在都会使硬质合金形成脆性断裂,直接影响合金的抗弯强度。  相似文献   

3.
本文研究了添加微量Y2O3对WC-8Ni硬质合金物理机械性能和显微结构的影响。研究发现Y2O3对合金的密度、硬度影响不大,但抗弯强度、耐磨性提高幅度较大,分别为50.4%和82.7%,达到并超过YG8合金性能。利用显微分析方法观察到Y相微粒弥散分布在Ni相和WC与Ni的相界处;过量Y2O3会生成Y的聚集相;WC晶粒均匀、细化;孔隙度降低;α-W2C相消失。讨论了Y2O3对显微结构影响的机理。  相似文献   

4.
研究了配碳量与Ni/Co比对WC-9(Ni-Co)硬质合金抗率强度的影响。实验结果表明:WC-3Ni-6Co的配碳量是6.04wt%时,其抗弯强度与WC-9Co硬质合金相当;Ni的分布均匀性对抗弯强度的影响极其重要,粗粒Ni粉或(和)较多η相的存在都会使硬质合金形成脆性断裂,直接影响合金的抗弯强度。  相似文献   

5.
本文叙述了WC-Co硬质合金特别是YG25牌号硬质合金的渗硼淬火热处理强化工艺和不同钴含量的合金的强化处理效果以及强化处理的合金应用效果,并对其强化机理进行了讨论。  相似文献   

6.
WC—8(Fe/Ni/Co)R硬质合金的研究   总被引:1,自引:0,他引:1  
用Fe、Ni部分取代WC-8Co合金(牌号YG8)中的粘结剂Co,再添加微量稀土R制得WC-8(Fe/Ni/Co)R硬质合金,测试了其物理机械性能,研究了粘结剂各种成份比例及烧结温度对硬质合金的影响。结果表明:WC-8(Fe/Ni/Co)R硬质合金的性能可以达到YG8的性能标准。利用扫描电镜(SEM)及X射线衍射(XRD)对其作了显微结构分析,同时探讨了影响WC-8(Fe/Ni/Co)R合金性能的  相似文献   

7.
热处理对硬质合金顶锤性能和结构的影响   总被引:1,自引:1,他引:0  
研究了热处理对硬质合金各项性能的影响以及顶锤内部钴粘结相成分和结构的变化。结果证明热处理可提高硬质合金的抗弯强度、抗压强度和顶锤表层的钴粘结相固溶度及面心立方钴含量 ,从而使顶锤的使用性能得到提高  相似文献   

8.
WC-Co硬质合金离子束表面改性研究   总被引:6,自引:0,他引:6  
研究了注入不同剂量Mo,Mo+C离子及Ti,Ti+Y离子的WC-Co硬质合金的硬度、成分及相组成的变化,经离子注入后,材料表面硬度显著提高,其中双元注入比单元注入效果要好,相分析表明,离子注入使WC晶面间距增大,稀土元素Y的注入在材料表面形成了Y的氧化物膜层。  相似文献   

9.
研究了准分子激光辐照对WC-6wt%Co(YG6)硬质合金工具衬底沉积金刚石膜的影响。证实准分子激光辐照可产生钴选择性蒸发和表面粗糙化;从而有效地降低表面钴含量,消除钴对金刚石膜沉积的有害影响。硬质合金YG6工具衬底沉积金刚石薄膜工艺参数范围较窄,采用阶段沉积法可以得到质量良好,附着力强的金刚石薄膜。  相似文献   

10.
探讨了淬火热处理对WC-co硬质合金性能影响的机理。查明了淬火既改变WC-CO合金γ相的成分和合金的应力状态,也改变合金的显微结构参数(其变化程度与WC的平均晶粒度有关)。考查了We-Co合金淬火效果在合金制品实际应用过程中的稳定性从而指出了WC-Co合金淬火热处理的实用意义。  相似文献   

11.
吴玉梅  熊晓云  靳蓉  孙敬民  杨林  罗晓星 《金属学报》2005,10(10):1100-1103
目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。  相似文献   

12.
The rheology feature of Sb, Bi melt and alloys was studied using coaxial cylinder high-temperature viscometer. The results showed that the curve of torsion-rotational speed for Sb melt presents a linear relation in all measured temperature ranges, whereas for the Bi melt, the curve presents obvious non-Newtonian feature within the low temperature range and at relative high shear stress. The rheology feature of Sb80Bi20 and Sb20Bi80 alloy melts was well correlated with that of Sb and Bi, respectively. It is considered that the rheology behavior of Sb melt plays a crucial role in Sb80Bi20 alloy and that of Bi melt plays a crucial role in Sb20Bi80 alloy.  相似文献   

13.
The effect of heat treatment on the microstructures and mechanical properties of a newly developed austenitic heat resistant steel(named as T8 alloy) for ultra-supercritical applications have been studied. Results show that the main phases in the alloy after solution treatment are γ and primary MX. Subsequent aging treatment causes the precipitation of M_(23)C_6 carbides along the grain boundaries and a small number of nanoscale MX inside the grains. In addition, with increasing the aging temperature and time, the morphology of M_(23)C_6 carbides changes from semi-continuous chain to continuous network.Compared with a commercial HR3C alloy, T8 alloy has comparable tensile strength, but higher stress rupture strength. The dominant cracking mechanism of the alloy during tensile test at room temperature is transgranular, while at high temperature, intergranular cracking becomes the main cracking mode, which may be caused by the precipitation of continuous M_(23)C_6 carbides along the grain boundaries. Typical intergranular cracking is the dominant cracking mode of the alloy at all stress rupture tests.  相似文献   

14.
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   

15.
16.
《中国铸造》2014,(6):540-541
Organized by Suppliers China Co., Ltd and co-organized by the National Technical Committee 54 on Foundry of Standardization Administration of China, the 15th Global Foundry Sourcing Conference 2014 (hereinafter referred to as FSC 2014) was successfully held on Sep. 23rd in Grand Regency Hotel, Qingdao. More than 500 delegates from home and abroad attended this conference, including over 130 purchasers from 20 countries and 380 domestic and foreign suppliers.  相似文献   

17.
By rolling and nitriding processes, 0.23- to 0.3-mm-thick grain-oriented 6.5 wt% silicon steel sheets were produced. The core losses of grain-oriented 6.5 wt% silicon steel at frequencies ranging from 400 Hz to 20 k Hz were lower than that of the grain-oriented 3 wt% silicon steel with the same thickness by 16.6–35.8%. The secondary recrystallization behavior was investigated by scanning electron microscopy, energy-dispersive spectroscopy, and electron backscattered diffraction. The results show that the secondary recrystallization in high-silicon steel sheets develops more completely as the nitrogen content increases after nitriding, secondary recrystallized grain sizes become larger, and the sharpness of Goss texture increases. Because more {110}116 grains in the subsurface and the central layer of the sheets have a lot of 20°–45° high-energy boundaries in addition to Goss grains, {110}116 can be the main component through selective growth during secondary recrystallization when the inhibitor quantity is not enough and inhibitor intensity is weaker. The increases in nitrogen content can increase the inhibitor intensity and hinder abnormal growth of a mount of {110}116 grains and therefore enhance the sharpness of Goss texture.  相似文献   

18.
Laser Cladded TiCN Coatings on the Surface of Titanium   总被引:3,自引:0,他引:3  
Laser cladded coatings of TiCN were produced on the surface of titanium. To obtain the optimal techniques, several conditions were tested by varying the laser scanning rate. The choice of shielding gas was also studied. The cladded coatings were then evaluated from the surface mechanics point of view based on their microhardness. The microstructure of some interesting samples was investigated by optical micrographs (OM). The results showed that under the condition of fixed pulse frequency and pulse width, the laser scanning rate and the shielding gas are the main factors influencing the components of coatings. TiCN coatings were decompounded and oxidized during the cladding process in the condition of no shielding gas of N2. X-ray diffraction results indicated that the composite coatings composed of TiCN, TiC, Ti2N, and TiO2 were produced using appropriate techniques. The results indicated that the best condition in terms of the surface microhardness is obtained when the scanning rate is 1.5mm / s, the pulse frequency is 15Hz, the pulse width is 3.0ms, and N2 is chosen as the shielding gas. The microhardness of the composite coatings is about 1331kg · mm - 2, which is about 4 times that of the substrate. The optical micrographs indicated that the cladding zone is made up of TiCN, TiO2, and some interdendritic Ti, but the diffusion zone mainly consists of the dendrites phase, and the cladded depth is about 80?滋m, which is more than 2 times that of the laser nitrided sample. There were no microcracks or air bubbles in the cladded sample, which was cladded using the above optimal techniques.  相似文献   

19.
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   

20.
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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