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1.
化学镀Ni-B合金镀层的微观结构   总被引:1,自引:1,他引:0  
采用XRD和TEM方法研究了5种化学镀N i-B合金镀层镀态下的微观组织结构,以及还原剂KBH4含量对镀层微观组织的影响。XRD分析表明,N i-B合金镀层主要为非晶态结构。TEM分析表明,N i-B合金镀层为非晶与纳米晶组合的混晶态结构,而且随镀液中KBH4含量的增加,N i-B合金镀层中的非晶态组织增加,纳米晶态组织减少,经历由纳米晶态→混晶态→非晶态的转变过程。采用XRD和TEM相结合方式,才得到准确的分析结果。  相似文献   

2.
采用机械球磨晶态Ti_3Ni_2(Ti2Ni/TiNi)合金的方法制备非晶态的Ti_3Ni_2合金,并研究其电化学性能。充放电测试结果显示,非晶态Ti_3Ni_2合金成功地解决了晶态Ti_3Ni_2合金在高温下(333K)循环寿命极短的缺点。在333K循环19次后,相对于晶态Ti_3Ni_2合金较低的容量保持率(39.47%),其非晶态合金有效的将容量保持率提高到88.83%。通过Tafel极化,线性极化以及交流阻抗测试,发现这种改善源于非晶态Ti_3Ni_2合金的耐蚀性远优于其晶态合金。  相似文献   

3.
采用机械球磨晶态Ti3Ni2 (Ti2Ni/TiNi)合金的方法制备非晶态的Ti3Ni2合金,并研究其电化学性能.充放电测试结果显示,非晶态Ti3Ni2合金成功地解决了晶态Ti3Ni2合金在高温下(333 K)循环寿命极短的缺点.在333K循环19次后,相对于晶态Ti3Ni2合金较低的容量保持率(39.47%),其非晶态合金有效的将容量保持率提高到88.83%.通过Tafel极化,线性极化以及交流阻抗测试,发现这种改善源于非晶态Ti3Ni2合金的耐蚀性远优于其晶态合金.  相似文献   

4.
应力松驰与非晶太Fe79B16Si5合金磁性优化   总被引:1,自引:0,他引:1  
车晓舟 《金属学报》1995,31(9):B418-B422
分析了退火过程中应力的松驰与非晶态合金磁性优化之间的联系,淬态Fe79B16Si5非晶合金经退火后,饱和磁感应强度Bs提高了72%,最在磁导率μm提高22倍,矫顽力Hc和功率P(0.3T,10kHz)分别降低86%和83%,退火过程吕条带内应力的松驰,有效地去除了应力感生磁各向异性,使非晶态合金的磁性得到显著优化。  相似文献   

5.
分别采用XRD和TEM分析方法对化学镀Ni-B合金镀层不同状态下的微观组织结构进行了比较研究.结果表明,Ni-B合金镀层主要为非晶态结构,随热处理温度升高,镀层逐步由非晶态向晶态转变.TEM分析表明,Ni-B合金镀层为非晶与纳米晶组合的混晶态结构,非晶镀层经350℃热处理以后转变为晶态镀层.比较研究发现,化学镀Ni-B合金镀层微观结构的分析必须采用XRD分析和TEM分析相结合的方式,才能得到准确的分析结果.  相似文献   

6.
论述了金属晶态-非晶态相变材料热力学与动力学的发展现状,对非晶态合金的整体研究现状进行分析。非晶态合金的热力学研究主要以稳定性为主,科研工作者对合金的热力学过冷区域、驱动力和晶化能力研究进行了完善;非晶态合金的动力学研究主要是以晶化过程为主,运用密度泛函数、DSC等技术对晶态-非晶合金相变过程的生长过程、玻璃转变温度、晶化激活能进行研究。  相似文献   

7.
采用XRD和TEM研究了热处理对化学镀Ni-B合金镀层微观组织结构的影响。XRD分析表明,Ni-B合金镀层主要为非晶态结构,随着热处理加热温度的不断升高,镀层逐步由非晶态向晶态转变。TEM分析表明,Ni-B合金镀层为非晶与纳米晶组合的混晶态结构,非晶镀层经过350℃热处理以后转变为晶态镀层。  相似文献   

8.
非晶态镍磷合金的组织结构与性能   总被引:21,自引:3,他引:18  
研究了化学沉积非晶态镍磷合金的组织结构与性能。结果表明,随着沉积层中磷含量的增加,合金的非晶化趋势提高,非晶态镍磷合金层的硬度和耐磨性能下降,且明显低于晶态镍磷合金;经过大于613K的时效处理,非晶态镍磷合金晶化且有Ni3P生成,沉积层的硬度和耐磨性得以提高并超过晶态合金;非晶态镍磷合金经过时效处理晶化后且组织结构发生变化,耐腐蚀性能下降,硬化性能则提高。  相似文献   

9.
硼含量对化学镀镍硼合金层组织和性能的影响   总被引:2,自引:0,他引:2  
本文研究了硼含量与化学镀镍硼合金层组织和性能的关系。结果表明,硼含量对镍硼合金层的表面形貌影响不大。硼含量低的合金层为晶态;随硼含量的增加,其结构逐渐转变为非晶态。晶态镍硼镀层的显微硬度比非晶态镀层的高,其耐磨性也优于非晶态镀层。  相似文献   

10.
车晓舟 《金属学报》1995,31(21):418-422
分析了退火过程中应力的松驰与作晶态合金磁性优化之间的联系淬态Fe_(79)B_(16)Si_5非晶合金经退火后,饱和磁感应强度B、提高了72%,最大磁导率μ_m提高22倍,矫顽力H_c和功率损耗P(0.3T,10kHz)分别降低86%和83%。退火过程中条带内应力的松驰,有效地去除了应力感生磁各向异性,使非晶态合金的磁性得到显著优化。  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
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   

14.
Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.  相似文献   

15.
The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.  相似文献   

16.
The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.  相似文献   

17.
On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes' collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.  相似文献   

18.
An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.  相似文献   

19.
A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.  相似文献   

20.
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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