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1.
在ENEPIG表面涂覆新工艺中引入了化学镀钯层,从反应原理上杜绝了镀镍层的氧化,在化学镀金过程中阻挡了镀镍层与浸金溶液的接触、镍的扩散和迁移,从而有效地抑制镍表层的氧化,防止"黑垫"缺陷产生。给出了该工艺量产的流程及参数控制,运用SEM和EDS对产品进行了微观形貌及扩散性分析。结果发现,钯层是非结晶状的皮膜,具有很好的镀层厚度均一性,并且在金表面没有发现镍的扩散。从而成功地实现了ENEPIG电路板的量产,替代了ENIG工艺。  相似文献   

2.
对常用的典型模具材料选取不同的工艺参数,对其表面进行激光淬火,取样后进行金相组织照片采集、淬火层层深及显微硬度检测分析。经试验结果对比分析,进而得出淬火层的性能与其微观组织以及激光淬火工艺参数三者之间的相互影响规律。为获得较理想微观组织分布和性能优异的淬火层提供了坚实的实验基础,使激光淬火技术在模具的表面强化处理上获得更好的应用。  相似文献   

3.
在零件表面进行渗氮工艺研究过程中,渗氮化合层的检测尤为重要.为了研究如何提高化合层检测制样的质量.文章首先分析比较热镶嵌工艺与冷镶嵌工艺对渗氮层试样制作质量的影响,然后又进一步对试样加工过程中抛磨速度和方向、抛磨压力和时间等诸因素进行试验分析,最终获得结论是:在表面渗氮工艺研究过程中,化合层检测试样宜采用热镶嵌,对于直径30mm的热镶嵌试样,采用450r/min-500r/min的转速、10N的压力、单向磨抛2.5min-3min,是较理想的工艺参数.渗氮层检测制样效果经验证合格.  相似文献   

4.
采用均匀设计液相涂覆热扩散方法,研究了涂覆离子,热扩散条件等对SrTiO_3系陶瓷电性能的影响;用扫描电子显微镜(SEM)和透射电子显微镜(TEM)作微观分析,用X射线能谱仪和电子探针(EPA)作元素分析,证实钠离子(Na~ )的涂覆热扩散未在陶瓷晶粒之间产生新相,钠离子(Na~ )在晶粒内表面形成了一扩散层,讨论了扩散条件与电性能的内在联系.  相似文献   

5.
垃圾邮件是Internet上面临急待解决的问题.Rough集理论是处理模糊和不精确数据的新型工具,能提供描述正常模型的最小预测规则集.重点阐述了Rough set在垃圾邮件过滤中的应用,并对大量数据进行了实验对比,试验验证了Rough set在垃圾邮件过滤技术上的可行性和可靠性.  相似文献   

6.
用SOL-GEL法在平板玻璃上涂覆彩色薄膜,对其技术工艺和制备条件进行了实验研究,利用正硅酸乙酯(TESO)的水解和添加着色剂的方法,获得了五种以上不同色泽的玻璃薄膜,在电炉上加热30分钟,所得薄膜非常牢固,而且色彩艳丽,对已有成膜技术和彩色膜配方进行了验证,并且作了改进,最后对制备过程和实验技术进行了讨论。  相似文献   

7.
针对工程应用中的高强螺栓表面硬度低、涂层结合力差、易脱落等问题,设计了热处理与表面处理对高强螺栓用钢性能影响研究的综合型实验。对35CrMo钢进行870℃×25min淬火,再经500℃×1h+550℃×1h回火的35CrMo钢,分别达到了制备12.9级和10.9级高强螺栓标准,对其进行渗N处理后,表面硬度达到了850HV,比心部显著提升。对渗N后的35CrMo钢表面涂覆锌铝溶液,其耐蚀性得到显著提升。该实验涉及材料热处理实验工艺和材料表面处理实验工艺,还涉及金属材料组织和性能测试的常用分析手段,是科研辅助教学的典型案例。  相似文献   

8.
对一种超小型铌合金泵浦激光器试制过程中出现的光斑问题进行分析和改进.采用试验方法,对出现的因光学元件产生反射杂光,光学元件表面破损或污染等出现多种杂光现象进行归纳分析,提出消除滤光片上、下表面反射杂光等相应的设计改进和工艺改进方法,并通过实验验证,有效消除其中大部分杂光,提高输出的激光束质量,提高成品率.  相似文献   

9.
该项目是为解决水库坝基深厚砂卵石层的防渗问题而提出的,是科研与生产相结合的实例.通过试验研究,可以把成功的理论及经验直接应用到水库大坝砂卵石层基础的防渗处理上,同时通过该工程的基础处理效果,可进一步验证理论的科学性和可靠性,以及将来的可推广价值.  相似文献   

10.
介绍了便携式计算机电磁兼容的一些基本概念、相关标准,提出了电磁兼容设计的思路及方法,重点阐述了电磁兼容性设计在便携式计算机设计中的应用.并结合便携式计算机的特殊性及在实际工作中所遇到EMC问题进行了特别说明.经实验验证该设计方法能够改善系统的电磁兼容性,提高了系统的可靠性.  相似文献   

11.
为了进一步研究化学镀镍磷复合镀层的性能,在研究了镍磷化学复合镀新配方的基础上,在A3钢片表面分别制备了纳米和微米复合材料镀层N i-P-MgO(CuO).用称重法测定厚度;通过10%NaC l溶液测定其耐腐蚀性;GB5935 86标准贴滤纸法测镀层的孔隙率;MH-3硬度仪测定其硬度.结果表明:在最佳施镀条件下,可得到耐磨性、硬度强于A3钢片、N i-P镀层和N i-P-MgO(CuO)纳米复合镀层的微米复合化学镀层,和光亮致密耐腐蚀性强于A3钢片、和N i-P-MgO(CuO)微米复合镀层,与N i-P镀层相当的N i-P-MgO(CuO)纳米复合镀层.  相似文献   

12.
采用化学镀法,以联氨作为还原剂,在螺旋碳纤维表面沉积金属镍,获得一种新的复合功能材料。通过SEM和EDX能谱分析,碳纤维基体上包覆了一层致密均匀而且连续的纯金属镍层,没有引入其它杂质元素。通过对样品在2~18 GHz范围内的电磁参数进行分析讨论,可知表面金属化一定程度上提高了样品的介电损耗,尤其在10~18 GHz有较大增幅,最大达到了35.2左右,表面金属化对样品的电阻率产生了不可忽略的影响,并且在低频处复合材料的电磁损耗都较纯基体材料有较大提高。  相似文献   

13.
本文研究了在稳定剂存在的条件下,在钢铁表面制备了Cu-Sn-P多元合金化学镀层,讨论了镀液成分和沉积条件等对镀层性质的影响.采用了硬脂酸、月桂酸和苯并三氮唑对Cu-Sn-P镀层表面进行再处理,从而形成致密保护膜,得到Cu-Sn-P/stearic acid(lauric acid,BTA)镀层,并研究了其性能.  相似文献   

14.
电火花沉积工艺(ESD)是一种微弧焊工艺,电极材料沉积到基体表面,并于基体呈冶金结合.本文以冷作模具钢Cr12MoV为基体材料,利用电火花沉积对局部区域进行修复.研究了影响沉积层质量和沉积率的工艺参数,其中包括电容、电压和保护气.实验结果显示,虽然随着电容和电压的增大,沉积率提高,但同时也会使沉积层中的微裂纹和孔洞增加.因此,只有合理选择沉积工艺参数,才能达到一定沉积率的同时保证沉积层的质量.  相似文献   

15.
以老旧沥青公路路面结构层水稳冷再生施工技术为研究对象,通过分析水稳冷再生施工技术的应用原理和应用过程,得出路面结构层水稳冷再生施工技术在老旧沥青公路改造和修复施工应用时,具有工程量比较小、施工工期短、可大幅度节约成本等优势。但施工工序比较多,需对各道工序严格控制,以提升路面结构层水稳冷再生施工技术应用水平的结论。基于此,文章以固原市硝口村309国道为例,分析了此项技术的应用过程,并提出几点心得体会。老旧沥青公路路面修复难度较大,传统全部铲除再铺筑,费时费力。采用路面结构层水稳冷再生施工技术,可有效解决这一问题,既能恢复老旧沥青公路的性能,还能降低修复成本,值得大范围推广应用。  相似文献   

16.
INTRODUCTION The elastic properties of coating layers in coating materials are very important in the design and evaluation for engineering purpose. They can serve as ground knowledge in the selection of surface coatings for particular applications, and can be used to monitor the quality of physical processes (Every, 2002). Therefore, estimation of the elastic properties of coating layers is of great practical value. Much effort has been put into measuring the material properties of coatin…  相似文献   

17.
Objective:To coat a zirconia surface with silica-zirconia using a dip-coating technique and evaluate its effect on resin-zirconia shear bond strength(SBS).Methods:A silica-zirconia suspension was prepared and used to coat a zirconia surface using a dip-coating technique.One hundred and eighty-nine zirconia disks were divided into three groups according to their different surface treatments(polishing,sandblasting,and silica-zirconia coating).Scanning electron microscopy(SEM),energy dispersive X-ray(EDX),and X-ray diffraction(XRD)were used to analyze the differently treated zirconia surfaces.Different primer treatments(Monobond N,Z-PRIME Plus,and no primer)were also applied to the zirconia surfaces.Subsequently,180 composite resin cylinders(Filtek Z350)were cemented onto the zirconia disks with resin cement(RelyX Ultimate).The SBS was measured after water storage for 24 h or 6 months.The data were analyzed by two-way analysis of variance(ANOVA).Results:SEM and EDX showed that the silica-zirconia coating produced a porous layer with additional Si,and XRD showed that only tetragonal zirconia was on the silica-zirconia-coating surface.Compared with the control group,the resin-zirconia SBSs of the,andblasting group and silica-zirconia-coating group were significantly increased(P<0.05).The silica-zirconia coating followed by the application of Monobond N produced the highest SBS(P<0.05).Water aging significantly reduced the resin-zirconia SBS(P<0.05).Conclusions:Dip-coating with silica-zirconia might be a feasible way to improve resin-zirconia bonding.  相似文献   

18.
The preparation of calcium phosphate (CP) coating on alumina ceramics using electric pulse stimulating method has been investigated. The cup-shaped alumina ceramics were soaked in a simulated body fluid ( SBF), and a square pulse potential with frequency of 1 Hz and voltage of 110 V was applied between the inner and outer surfaces of the alumina cup. Surface morphology of CP coatings during different deposition periods was observed by a Philips XL-30 scanning electron microscope (SEM). Compositional analysis was examined by EDAX. The mechanism of nucleation and growth of CP coating was discussed. SEM result indicates that the coating comprises of a large number of tiny needle-like grains and has a porous microstructure. There is a strong bond between the deposited layer and Al2O3 substrate, which may be due to the gentle growth of the biomimetic method. The EDAX analysis indicates that main composition of the coating is calcium and phosphor. The formation of CP coating may be contributed to the stimulation of electric pulse and the high ions concentration which is 1.5 times of the concentration of SBF solution ( 1.5SBF solution). Such surface functionalization method by electric pulse potential can be used to prepare CP coating on various electric-insulating bioinert materials for improving their bioactive character.  相似文献   

19.
PREPARATION AND CHARACTERISTICS OF NEW TYPE NANOCOMPOSITE POWDER   总被引:4,自引:0,他引:4  
INTRODUCTIONTheauthor’spastresearchesshowedthatelectroless platedmetal ceramiccompositepow dercouldretardceramicgaingrowthduringthesinterprocess,evenlydispersethemetallicphaseontheceramicmatrixand ,therefore ,in creasethefracturestrength ,toughnessandwear…  相似文献   

20.
This paper introduces a new technology of using ceramic coating on piston tings of an internal combustion engine, and the comparison of mechanical efficiency and performances of an actual engine before and after the application of ceramic coating on the piston rings. The experimental results show that the mechanical efficiency and power output are enhanced by 4% and 2.6%, respectively, with fuel consumption reduced by 2.9%. Further studies on coating processing and coating materials as well as the reliability and durability will be of great significance in the application and popularization of the new technology.  相似文献   

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