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61.
Stannate and permanganate conversion coatings on AZ31 magnesium alloy   总被引:4,自引:1,他引:4  
The formation of stannate and permanganate–phosphate conversion coatings on AZ31 magnesium alloy was investigated in situ by EIS measurements and their protective performances were studied by different electrochemical techniques in diluted (0.05 M) sodium sulphate solution.The influence that short or long treatment times exert on the performances of such conversion coatings is discussed. While permanganate–phosphate baths always built layers characterized by penetrating cracks, long stannate baths produced layers without interconnected porosity, but were defective. This accounted for the initial greater protectiveness achieved with the stannate treatment; nevertheless, the easy penetration of the electrolytic solution through such a layer quickly decreased its corrosion resistance.  相似文献   
62.
余新惠 《表面技术》1989,18(6):28-32
通过炮用弹链粉末静电喷涂工艺试验,验证了弹链粉末涂装的可行性。粉末涂装工艺能够提高炮用弹链的防蚀性,简化工序。  相似文献   
63.
In this study, a kind of imidazole type poly(ionic liquid) ([PEP-MIM]Cl) is synthesized, which can disperse carbon effectively. [PEP-MIM]Cl is used as an intermediate to coat carbon on the poly(acrylic acid)(PAA-co-MBA) via ion exchange to obtain conductive polymer composite (CPC). A series of characterizations are performed. Experiments show that carbon can be coated on the PAA-co-MBA uniformly, and compared with using carbon as filler, this method requires less carbon to achieve good conductive performance. The carbon layer on the polymer's surface is enriched via the swelling-shrinking properties of PAA-co-MBA according to the SEM images. Furthermore, in combination with 3D printing technology, PAA-co-MBA can be designed into different shapes to achieve various functions such as pressure-sensing element. Finally, a new type of CPC named carbon clad polymeric laminate (CCPL) is prepared by using the carbon coating method and 3D printing technology. It has the potential to replace copper clad laminate (CCL) and printed circuit board (PCB), to a certain extent. This technology expands the preparation method and application of the CPC such as flexible and wearable conductive fabrics.  相似文献   
64.
The microstructural features of cold-sprayed coatings were investigated using Cu, Ti and Zn feedstocks by optical microscopy, scanning electron microscopy and transmission electron microscopy to reveal the microstructure evolution mechanisms in cold spray. Four typical effects including tamping, refinement, impact-induced fusion and annealing were examined on microstrueture. It is found that the microstructure of cold spray coating is remarkably influenced by spray materials. Ti coatings consist of evident porous layer and Cu coatings present a limited porous layer only near the surface. It is clear that the successive tamping effect and dynamic refinement of grains significantly influence the microstructure evolution of cold-sprayed coating. The tamping effect leads to the densification of porous coating layer gradually and the refinement effect leads to the formation of fine microstructure. It is considered that the large difference in the formation of porous layer is attributed to the dynamic impact pressure and hardenability of materials. It is also found that the impact-induced fusion during deposition of Zn coating can also modify the interfacial microstructure between particles in cold spray coating. Moreover, the nanocrystalline phase can be formed at the interfaces among particles resulting from the localized melting of the interfaces and tamping effect. Furthermore, the annealing treatment can modify the microstructure and property of a cold-sprayed coating.  相似文献   
65.
张世宗 《铸造技术》2004,25(6):424-424,426
叙述101强化粉在涂料中的应用,测定涂料的性能,研究101水基涂料对砂芯的渗透性,防止铁液浸渗的作用.生产结果令人满意.  相似文献   
66.
聚苯硫醚的性能及在防腐蚀涂层上的应用   总被引:3,自引:0,他引:3  
李建康 《腐蚀与防护》2004,25(4):164-167
较详细地介绍了聚苯硫醚(PPS)的性能、发展概况及在防腐蚀领域的应用前景。根据实践经验叙述了PPS的喷涂工艺,总结分析了影响PPS涂层施工质量的主要因素及解决办法。  相似文献   
67.
熔渣法碳化铬涂层的抗氧化性能研究   总被引:1,自引:0,他引:1  
对熔渣法碳化铬涂层在各种温度下经20h和200h的氧化性能进行了研究,与常用的一些锅炉用钢进行了对比试验,结果表明碳化铬涂层抗氧化性能比15CrMo、102、T91钢好,可以与TP347钢相媲美。  相似文献   
68.
Chromium oxide coatings were deposited by reactive magnetron sputtering on high speed steel (HSS) substrate under various oxygen flow rates and radio frequency (RF) powers. The effect of deposition conditions on the microstructure, hardness and critical load of chromium oxide coating failure was studied. The results indicated that a crystalline chromium oxide coating formed at a high oxygen flow rate and a low RF power exhibited a higher hardness and a lower critical load as compared to a chromium oxide coating with an amorphous microstructure.  相似文献   
69.
Fabrication of composite wire of lead coated on glass fiber by extrusion   总被引:1,自引:0,他引:1  
1 INTRODUCTIONCoatingglassfiberwithleadproducesakindofnewcontinuouscomposite ,whichcanfindwideap plicationsinmanydifferentfields ,especiallyinthebatteryoftheEVsandHEVsthathasalreadybecomethemostimportantgoalinmostcountries[13] .Withakindofspecialtechnologythiskindofnewcompos itewirecanbeusedtoproducegridsofnewleadacidbatterythatisveryusefultotheEVsandHEVs .Thiskindofnewleadacidbatteryhasmanyadvan tages ,suchashigherspecificenergy ,lessinnerresis tance ,morequicklychargingcapabilityand…  相似文献   
70.
压入深度与膜厚对薄膜与基体复合硬度及弹性模量的影响   总被引:2,自引:0,他引:2  
根据高华建的复合弹性模量模型,提出了用一个测点的载荷-位移曲线计算整个压入深度内薄膜和基体复合硬度分布的方法,探讨了压入深度与膜厚对硬度与弹性模量测量值的影响,指出可由膜-基复合性能反推膜本身的性能。  相似文献   
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