首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
王虎  朱延玲 《表面技术》2019,48(11):211-218
目的在CNTs表面镀上一层均匀分布的铜镀层,以此优化CNTs在金属基体中的润湿性,提高CNTs与金属基体之间的界面结合力,实现CNTs在金属基体中的均匀分散,为制备高性能金属基复合材料提供途径。方法首先对CNTs进行预处理,包括纯化、氧化、敏化、活化,再进行表面化学镀铜,从而在CNTs表面获得均匀分布的铜镀层。采用扫描电镜(SEM),透射电镜(TEM)、拉曼光谱(Raman)等测试方法对不同处理后的CNTs进行微观组织表征。结果 CNTs经过预处理后,实现了CNTs表面镀铜。同时,在化学镀铜过程中,铜镀层在CNTs表面的生长并不是一个持续稳定的过程,首先在活化程度较高的位置形核长大,再横向生长,最终覆盖整个CNTs表面。实验得到了CNTs镀铜的最佳参数:CuSO_4·5H_2O的质量浓度为18 g/L,镀铜时间为15 min。在此条件下,铜镀层的分布比较均匀,单根CNTs上不同部位的镀层厚度基本相同,铜镀层的平均厚度为25 nm。结论 CNTs经过预处理后,表面形成了含氧官能团,镀铜过程去除了CNTs表面的大部分官能团,并在其表面获得均匀分布的纳米级厚度的铜镀层,改善了CNTs在金属基体中的润湿性,为CNTs应用到金属基复合材料提供重要途径。  相似文献   

2.
Ti3SiC2陶瓷颗粒表面超声波化学镀铜   总被引:1,自引:1,他引:0  
钛碳化硅(Ti3SiC2)陶瓷导电材料有许多优异的性能,其摩擦系数甚至比石墨更低,完全可以取代石墨用来制备性能更加优良的铜基电接触复合材料,但是由于其与铜基体之间的浸润性不是很好,研究了利用超声波化学镀覆技术在Ti3SiC2颗粒表面均匀镀上一层连续的铜镀层。通过扫描电子显微镜对铜镀层表面形貌的观察表明:通过严格的镀前预处理工艺的优化设计以增加活化点,对传统镀液配方的调整以降低镀速,能够成功的在Ti3SiC2颗粒表面均匀镀覆一层铜微粒,改善了Ti3SiC2和铜基体间的润湿性,从而增强二者之间的界面结合力。  相似文献   

3.
电刷镀Ni-P-Al2O3-碳纳米管复合镀层工艺研究   总被引:2,自引:0,他引:2  
采用电刷镀的方法,在金属零件表面沉积一层Ni-P-Al2O3-碳纳米管复合材料。实验表明,通过对碳纳米管进行氧化、敏化和活化等预处理,可使碳纳米管颗粒均匀地分散在刷镀层中;施镀溶液温度应控制在55℃,pH值在1.5-2.5。碳纳米管的加入可有效地防止刷镀层裂纹、易剥落、结合强度低的缺陷。  相似文献   

4.
含镀铜石墨颗粒铜基复合材料研究   总被引:3,自引:0,他引:3  
采用化学镀铜工艺在石墨颗粒表面镀上一层金属铜,通过粉末冶金方法制备了铜/石墨复合材料,研究了石墨颗粒表面铜镀层在不同处理温度下的球化问题和改善复合材料界面结合的作用效果.结果表明,石墨颗粒表面铜镀层有利于改善铜基石墨复合材料的界面结合,使复合材料力学性能提高;处理温度较高时,表面铜镀层有熔融球化的趋势,当复合材料烧结温度超过石墨镀铜层的完全球化温度时,镀铜石墨粉改善界面结合的效果逐渐降低,直至消失.  相似文献   

5.
采用真空微蒸发-扩散镀技术,在金刚石表面镀覆不同厚度的钨层,并结合真空熔渗法制备金刚石铜复合材料。通过X射线衍射分析镀覆层相结构,采用扫描电镜观察镀覆层表面微观形貌和复合材料中金刚石与铜界面结合形貌,分析金刚石表面镀钨层组织、结构及厚度对金刚石/铜复合材料热导率的影响。结果表明:金刚石表面镀覆钨能改善与基体的润湿性;随着镀覆层均匀性和厚度增加,复合材料热导率先增加后减小;完整均匀的镀覆层可以获得较高界面热导。  相似文献   

6.
温度对碳化硅粉体表面镀镍的影响   总被引:3,自引:3,他引:0  
姚怀  许波  王永志 《表面技术》2011,40(6):71-73
为改善碳化硅陶瓷粉体与金属的润湿性,在碱性条件下,以水合肼为还原剂,采用化学镀方法在 碳化硅粉体表面沉积镍层,结合镀层的表面形貌、组织结构和实验现象,研究了镀液温度对镀镍的影响,此外还研究了水合肼用量对镀速的影响.结果表明:反应温度为70,75,80℃时,所得包覆粉体的表面镀层由颗粒状、胞状的Ni组成,基体完全被镀层...  相似文献   

7.
文中报道了一种借助多巴胺在PEEK表面化学镀铜的方法。首先通过非溶剂致相分离法对PEEK表面进行粗化,形成网络状孔洞,然后借助多巴胺的自身氧化聚合在PEEK表面包覆聚多巴胺层,利用聚多巴胺对银离子的吸附和原位还原作用在PEEK表面沉积纳米银颗粒,纳米银颗粒作为催化中心催化化学镀铜反应的进行,从而在PEEK表面镀覆金属铜层。通过SEM、EDS、接触角测试、XRD表征复合材料的形貌、化学组成、润湿性和结晶形态,通过胶带剥离实验评估镀层结合力,使用四探针测试仪测量镀层的方块电阻。结果表明,纳米银可以有效地催化PEEK表面的化学镀铜反应,且镀液稳定,铜层与PEEK的结合力达到5B级;施镀时间为60 min时,由断面图测得的镀层厚度约为3.5μm,方块电阻低至19 mΩ/□。  相似文献   

8.
一种新型的碳纤维和碳纳米管化学镀镍工艺   总被引:5,自引:0,他引:5       下载免费PDF全文
碳纤维是最重要的复合材料增强体之一,而碳纳米管比碳纤维具有更好的力学性能,对他们的表面改性将会对复合材料性能有很大影响。试验实现了一种对碳纤维和碳纳米管通用的化学镀镍工艺。通过对基体较好的预处理,在基体上成功地完成了化学镀镍并且较好的控制了镀层成分。同时还探讨了施镀温度、pH值和搅拌方式等对镀层的影响,试验发现pH值控制在9~10之间,温度控制在70℃附近并采用氮气搅拌可以获得较满意的施镀效果。  相似文献   

9.
化学镀是ABS塑料表面金属化最常用的方法之一,但在施镀前需要使用钯等贵金属对基体进行活化,使其具有催化活性。以NiSO_4与NaH_2PO_2混合配制活化液,涂覆于塑料基体表面,常温放置8~10min后,基体表面形成一层活化层;用激光均匀扫描基体表面,活化层在激光作用下反应生成活性Ni微粒使基体活化,再进行化学镀镍。采用正交试验优化激光活化各参数,通过扫描电镜对各阶段基体表面形貌进行表征,利用能谱和X衍射对活化及施镀后的基体表面成分进行分析,采用高低温冲击法检测镀层结合性。结果表明,当NiSO_4与NaH_2PO_2浓度分别为10g/L和40 g/L,光斑直径为1mm,扫描速率为5 mm/s,涂覆次数为2次时,镀覆效果最好;基体活化后,表面附着一层均匀的平均直径为30nm的活性Ni微粒催化核心;施镀后,镀层均匀致密,结合性较好。  相似文献   

10.
镍基合金是一种难镀的基体,为了提高它与镀层的结合性能,基体采用阳极活化和预镀镍过渡层,获得的铜锡合金镀层与基体结合牢固,经试验元爆皮、剥落等现象.  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.
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   

13.
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   

14.
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   

15.
韩磊 《腐蚀与防护》2015,36(1):84-90,94
综述了常见的电化学噪声数据处理方法,介绍了直流趋势剔除、统计分析、快速傅立叶变换(FFT)法计算功率谱密度(PSD)以及小波变换处理电化学噪声信号的基本过程,并阐释了各种数学处理及所得参数的物理意义。  相似文献   

16.
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   

17.
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   

18.
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   

19.
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   

20.
正Harbin General Hydraulic Machinery Works Co.,Ltd.of Yilin Hydraulic Group is the most professional production base of large-scale metallurgy oil cylinder and oil machinery cylinder in the Northeast of China.The main products include metallurgy cylinder,swell-shrink cylinder,rotating injection device,lifting cylinder,main lifting jack,front lifting jack,engineering oil cyl-  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号