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通过对纳米复合材料镀层Cu—Sn—P—ZrO2的制备条件（包括浓度、时间、温度及pH）的研究,制得了光亮、致密且孔隙率低的镀层。用扫描电子显微镜（SEM）观察其外貌,称重法测定其厚度,并通过加速腐蚀实验等方法测定了其腐蚀性能。结果表明：由于纳米微粒的存在使得其耐腐蚀性能大大提高。 相似文献
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《实验室研究与探索》2017,(11)
用化学镀工艺获得了Ni-Mo-Cr-P合金镀层,研究了Ni-Mo-Cr-P非晶态合金膜随晶化处理温度升高,其结构以及耐蚀性的变化规律,并对变化的原因进行了分析。结果表明,镀态Ni-Mo-Cr-P为非晶态镀层,300℃时Ni_3P渐渐开始析出;400℃时Ni_3P相继续析出,Ni衍射峰变得较为尖锐;500℃,Ni晶化较为完全,同时出现新相Cr_(1.12)Ni_(2.88);600℃有Cr_2Ni_3,CuNi,Cu_(3.8)Ni和Mo_(1.24)Ni_(0.76)生成;700℃时出现Cu_(0.81)Ni_(0.19)和MoNi_3,Ni_3P发生再结晶,同时镀层开始氧化生成Ni O。电化学分析显示,镀态下Ni-Mo-Cr-P合金镀层的耐腐蚀性能优于Ni-P、Ni-Mo-P镀层;400℃下进行晶化处理,Ni-Mo-Cr-P镀层的耐腐蚀性有所提高,更高温度下的晶化处理,都会损害合金镀层的耐腐蚀性。 相似文献
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用电沉积方法制备了Fe-Ni-P合金,研究了NaH2PO2·H2O的浓度对镀层组分的影响,镀层中磷含量与合金结构的关系,用数字电桥测量了合金的电阻率.在高频(3000Hz)下,用三电压法测量了合金的磁导率,探讨了镀层中磷含量对合金软磁性能的影响,结构与性能的关系. 相似文献
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一、概述目前，国内外广泛采用光亮镀Sn－Pb合金解决电子元器件可焊性问题。光亮Sn－Ph合金镀层，其优点是抗氧化，可焊性好，表面光亮，外观装饰性好，但是，由于Sn－Ph合金镀液中，含有许多结构复杂的有机光亮剂，在电镀过程中，会不同程度地夹杂在电子元器件表面镀层中，其量过多，会造成在隧道炉熔焊时，受热变色，产生气泡、麻坑等，使镀层可焊性下降，外观装饰性变差。为了保持电镀液中光亮剂的适宜比例，应根据实际消耗量经常补充。在工业生产中，是通过赫尔槽试验或根据操作者的实践经验来估计补充量，很难做到准确控制。本文采… 相似文献
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专业综合创新实验是培养学生创新思维和实践能力的重要环节。基于材料成分-组织结构-制备工艺-性能之间的四要素关系,设计了本实验。利用金相显微镜和极化曲线技术,研究了锌浴中的Mn对0.04wt%Si钢热浸镀锌组织及耐蚀性能的影响。结果显示:当Mn的添加量达到0.5wt%时,Zn-Mn合金镀层在5%NaCl溶液中具有最佳的耐蚀性能。教学实践表明,该综合创新实验有利于学生综合分析问题、解决问题的能力,特别是创新能力的培养。 相似文献
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赵亚楠 《湖北广播电视大学学报》2011,31(7):156-157
本文采用溶胶—凝胶法先在铸件表面涂覆一层TiO2薄膜,再对铸件进行化学镀Ni—P处理。研究表明,TiO2涂层可以有效减小铸件表面的孔隙率,弥补了Ni—P镀层直接覆盖在铸件表面易产生针孔的缺陷。与现有的铸件表面处理方法相比,本工艺改善了铸件的耐腐蚀性,而且较大地提高了沉积速率。在不增加过多成本的情况下,还节约了能源。 相似文献
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针对镀锌钢板冲压件的开裂分层现象,利用扫描电镜和金相显微镜对分层试样进行断口观察和金相分析。结果表明：试样开裂分层的主要原因是其存在大量的夹渣和组织偏析。 相似文献
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分析了深冲合金化热镀锌钢DX53D＋ZF的镀层组织结构和微观成分,测试了试验钢的拉伸性能、成型性能和抗粉化性能特性。分析结果表明,产品具有良好的塑性应变性能,镀层厚度分布均匀;结构细小致密;镀层铁含量平均为10％,梯度变化平缓。 相似文献
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铱钴涂层钛阳极的组织结构与析氧性能 总被引：1，自引：1，他引：1
通过热分解法在制备了不同摩尔配比的IrCo氧化物涂层,并通过XRD分析了涂层的组织结构,通过循环伏安,析氧电位及强化寿命测试研究了 Ti 基 IrCo 涂层的电催化活性.结果表明,Co组元的添加可以明显细化活性组元 IrO2 的晶粒,有效降低涂层的析氧电位,当 w(Co)=30%铱钴涂层比纯铱涂层的强化寿命提高了40%. 相似文献
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Titaniumalloyisakindofdesirablemetallicbioma terialforimplantingandrepairingbodyhardtissuesduetoitsbetterbiocompatibilityandmechanicalproper ties[1,2 ] .However ,itcansuffercertaindisadvantages ,suchaspoorosteoinductive ,andlowcorrosivewearresis tance .So ,itisveryimportanttoimprovethejointprop ertiesbetweentitaniumalloyandhumanbody .Hydrox yapatite(HAP)isknowntobebiocompatibleandtoformadirectbondwiththeneighboringbonesduetoitscrys tallographicalandchemicalsimilaritywithvariouscalci fiedtissu… 相似文献
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The influence of direct quenching （DQ） on microstructure and mechanical properties of 0.19C-1.7Si-1.0 Mn-0.05Nb steel was studied. The microstructure and mechanical properties of reheat quenched and tempered （RQ＆T） steel plate were compared with those of direct quenched and tempered （DQ＆T） steel plates which were hot rolled at different finish rolling tem-peratures （1173 K and 1123 K）, i.e., recrystallization-controlled-rolled direct-quenched （RCR＆DQ） and controlled-rolled direct-quenched （CR＆DQ）, respectively. The strengths generally increased in the following order： RQ＆T〈RCR＆DQ＆T〈 CR＆DQ＆T. Strength differences between the CR＆DQ＆T and RQ＆T conditions as high as 14% were observed at the tempered temperature of 573 K. The optical microscopy of the CR＆DQ＆T steel showed deformed grains elongated along the rolling direction, while complete equiaxed grains were visible in RQ＆T and RCR＆DQ＆T steels. Transmission electron microscopy （TEM） and electron backscattering diffraction （EBSD） of the DQ steels showed smaller block width and higher density of dislocations. Inheritance of austenite deformation substructure by the martensite and differences in martensite block width were ruled out as major causes for the strength differences between DQ and RQ steels. 相似文献
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High-Temperature Corrosion of Protective Coatings for Boiler Tubes in Thermal Power Plants 总被引：4，自引：0，他引：4
High-temperature corrosion is a serious problem for the water-wall tubes of boilers used in thermal power plants. Oxidation, sulfidation and molten salt corrosion are main corrosion ways.Thereinto, the most severe corrosion occurs in molten salt corrosion environment. Materials rich in oxides formers, such as chromium and aluminum, are needed to resist corrosion in high-temperature and corrosive environment, but processability of such bulk alloys is very limited. High velocity electric arc spraying (HVAS) technology is adopted to produce coatings with high corrosion resistance. By comparison, NiCr (Ni-45Cr-4Ti) is recommended as a promising alloy coating for the water-wall tubes, which can even resist molten salt corrosion attack. In the study of corrosion mechanism, the modern material analysis methods, such as scanning electron microscopy ( SEM ), X-ray diffractometry (XRD) and energy dispersive spectrometry (EDS), are used. It is found that the corrosion resistances of NiCr and FeCrAl coatings are much better than that of 20g steel, that the NiCr coatings have the best anti-corrosion properties, and that the NiCr coatings have slightly lower pores than FeCrAI coatings. It is testified that corrosion resistance of coatings is mainly determined by chromium content, and the microstructure of a coating is as important as the chemical composition of the material. In addition, the fracture mechanisms of coatings in the cycle of heating and cooling are put forward. The difference of the thermal physical properties between coatings and base metals results in the thermal stress inside the coatings. Consequently, the coatings spall from the base metal. 相似文献
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用金属粉末注射成型的方法制备高硬度合金剪刀,其喂料使用440型不锈钢粉末和PEG/PMMA复合粘结剂制成。前人对该问题的研究主要集中在440型不锈钢粉末的PIM成型方法上,而本文结果表明:通过精确控制粉末的烧结条件和热处理工艺,就可以获得硬度高、粉末分布均匀、碳化物球化良好的制品。 相似文献
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Researchershavebecomeincreasinglyinterestedinironaluminideintermetallics (includingFe3AlandFeAl)since 1970sinviewofthecombinationoflowcost,lowerdensity ,remarkableresistancetoerosion ,sulfidizingandoxidizingathightemperature .However ,industrialap plicationofthesealloyshasbeenverylimitedduetotheirpoorductilityandfracturetoughnessatroomtemperatureaswellastheirdifficultyinshaping[1] .Somestudieshaveindicatedthatcoatingstructuralmaterialswithironaluminidesbyusingthermalsprayingwillnotonlysolveth… 相似文献
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利用电弧喷涂设备在低碳钢试件表面制备了0Cr18Ni9涂层,并在金相显微镜下观察涂层的显微组织结构,同时用拉伸试验机对不同厚度涂层的结合强度进行了测试。实验结果表明：涂层的成形良好,组织比较均匀;厚度对涂层与试件的结合强度有显著的影响,为保证涂层的使用性能,涂层厚度应不大于0.6mm。 相似文献