The Study of Electroless Ni-B Coating on 45 Steel

2012 ◽  
Vol 501 ◽  
pp. 185-189
Author(s):  
Jian Zhang Guo ◽  
Qian Liu

In order to improve the corrosion resistance and the hardness of the 45 steel, under comparison tests, the electroless Ni-B was prepared on the 45 steel. We made a contrast test to get the optimal formula. The coating under the optimal formula was characterized by Scanning Electron Microscopy(SEM), Energy Dispersive Spectrometer(EDS), metallurgical microscope and salt spray cabinet. The experimental results showed that the electroless Ni-B coating on 45 steel was low boron coating, with high hardness, and the hardness of the coating could catch HV524; the thickness of the coating was 16μm.

2012 ◽  
Vol 501 ◽  
pp. 316-320
Author(s):  
Jian Zhang Guo ◽  
Bin Xu

In order to improve the surface property of the steel tire mold, carbon steels were processed by electroless Ni-P and Ni-P-PTFE under contrast experiment. The coatings were characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS). The wear resistance and corrosion resistance of the coatings were explored by tribometer, salt spray cabinet and advanced electrochemical system. The experimental results showed that the Ni-P coating was amorphous structure, and the Ni-P-PTFE coating was micro-pore structure; The wear resistance of Ni-P-PTFE coating was superior to Ni-P coating; In view of the micro-pore structure, the corrosion resistance of Ni-P-PTFE coating was worse than Ni-P coating, but they were all superior to carbon steels, and the service life of the steel tire mold were improved.


2013 ◽  
Vol 364 ◽  
pp. 573-576
Author(s):  
Yuan Xing Cai ◽  
Zhong Kui Zhao ◽  
Zhi Gang Wang

Lithium was added into ZAlSi12 casting alloys to produce Al-Si-Li alloys containing 0%Li, 1%Li, 2%Li and 3%Li respectively. The corrosion performance of the alloys containing various content of lithium was tested by the Tafel polarization curves and the alloys were dipped thoroughly into the solution of 5% NaCl. The surface appearance of the alloys after corrosion was observed by Scanning Electron Microscopy, the composition of corrosion products was determined by Energy Dispersive Spectrometer. The results show that the corrosion resistance of ZAlSi12 casting alloys is improved by the addition of lithium. The alloy has an optimum corrosion resistance when the lithium content is 2%, and then the corrosion resistance decreases as increment of lithium content.


2006 ◽  
Vol 11-12 ◽  
pp. 421-424 ◽  
Author(s):  
Qin Xiu Lv ◽  
Xiao Feng Zhang ◽  
Yu Ming Tang ◽  
Jing Mao Zhao ◽  
Yu Zuo

With the certain deposition process, the conversion coatings by four different pretreatments on LF21 were studied. The morphology and the chemical composition of the conversion coatings were examined by scanning electron microscopy (SEM). The corrosion resistance was investigated by electrochemical impedance spectroscopy (EIS) and the salt spray test. The results showed that the different pretreatments had obvious effect on the cerium conversion coatings. For the certain deposition process, the optimal pretreatment process was identified.


2021 ◽  
Vol 325 ◽  
pp. 181-187
Author(s):  
Martin Nguyen ◽  
Radomír Sokolář

This article examines the influence of fly ash on corrosion resistance of refractory forsterite-spinel ceramics by molten iron as a corrosive medium. Fly ash in comparison with alumina were used as raw materials and sources of aluminium oxide for synthesis of forsterite-spinel refractory ceramics. Raw materials were milled, mixed in different ratios into two sets of mixtures and sintered at 1550°C for 2 hours. Samples were characterized by X-ray diffraction analysis and thermal dilatometric analysis. Crucibles were then made from the fired ceramic mixtures and fired together with iron at its melting point of 1535°C for 5 hours. The corrosion resistance was evaluated by scanning electron microscopy on the transition zones between iron and ceramics. Mixtures with increased amount of spinel had higher corrosion resistance and mixtures with fly ash were comparable to mixtures with alumina in terms of corrosion resistance and refractory properties.


2014 ◽  
Vol 971-973 ◽  
pp. 802-805
Author(s):  
Wei Feng Zhang ◽  
Li Yan ◽  
Fu Xia Zhang

For the problem of high-speed rotating centrifuge spindle fracture failures, relevant analyses are conducted from the perspective of microstructure, chemical composition and fracture mechanics by using scanning electron microscopy and related instruments. Experimental results and analyses indicate that the spindle fracture is fatigue failure, mainly caused by cold cracks generated on the journal surfacing. Based on the analysis results, improvements and measures are suggested to better solve the spindle weld fracture failure problems.


2012 ◽  
Vol 457-458 ◽  
pp. 146-149
Author(s):  
Yan Hai Cheng ◽  
Shi Ju Zhang ◽  
Yu Xing Peng ◽  
Fang Fang Xing ◽  
Jie Li ◽  
...  

In this study, Ni-P-SiC composite coatings were prepared by adding different amount of SiC particles into electroless Ni-P plating solution. The effects of SiC particles concentration in solution on depositing rate and composition of the coatings were investigated. The different SiC contents in coatings could be obtained by adjusting the amount of SiC particle concentration in electroless plating solution. Scanning electron microscopy (SEM) results indicate that SiC particles are dispersed in the composite coating and Ni-P alloy is mainly as a bond metal envelope with SiC particles. At the same time, the microhardness became increased and the wear resistance improved with the increasing of SiC content.


2012 ◽  
Vol 535-537 ◽  
pp. 996-999 ◽  
Author(s):  
Bao Feng Zhang ◽  
Qi Chen ◽  
Xiao Wei Chen ◽  
Hong Liang Zhao

In this study, the effect of KBF4 addition on the microstructure of the Mg-6Zn-1Si alloy has been investigated by Optical Microscopy (OM), Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrometer(EDS). At 1.5wt% KBF4 addition, the morphology of Mg2Si phase completely changed from Chinese script type into uniformly, dispersedly distributed graininess or small block, with the average size of the Mg-6Zn-1Si alloy decreasing from 135μm to 82μm.


Author(s):  
Xiaochun Li ◽  
Zhiwei Li

Permalloy NiFe matrix nanocomposite layers were electroplated on a copper substrate. The volume fraction of nano-sized Si3N4 particles in NiFe matrix was controlled by the addition of various percentages of Si3N4 particles in the NiFe electrolyte. The nanocomposite layers were analyzed by a scanning electron microscopy (SEM). Microhardness test was performed. With nano-sized Si3N4 particles in the NiFe matrix, the microhardness of NiFe was improved. The samples were then annealed at 800 °C for about 20 hours. The microhardness declined more with more Si3N4 particles in the NiFe matrix. The analysis result from Energy Dispersive Spectrometer (EDS) in the SEM showed that the hardness declination could be caused by the segregation of Si3N4 in the NiFe matrix. Finally this paper presents nanocomposite micromolds fabricated by electroplating onto polymer molds that were fabricated by micro-stereolithgraphy.


2011 ◽  
Vol 295-297 ◽  
pp. 869-872
Author(s):  
Qing Shan Li ◽  
Xin Wang ◽  
Jun Liu ◽  
Guang Zhong Xing

Six-ring Rock is widely used as containers of water and additives to produce health care products. In this paper, the composition and microstructure of Six-ring Rock have been investigated by using scanning electron microscopy, energy dispersive spectrometer, transmission electron microscopy, x-ray diffraction and other technologies. Results show that Six-ring Rock is composed of CaMg(CO3)2, SiO2 and KAlSi3O8. Fe atoms exist in CaMg(CO3)2 by replacing Mg atoms. Six-ring Rock shows nano-size lamellar and acerose microstructures on the surface, and nano-size monocrystals in the body. Six-ring Rock is a natural nano structure mineral.


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