Structure and Properties of the Surface Layer of a Wear-Resistant Coating on Martensitic Steel after Electron-Beam Processing

2017 ◽  
Vol 906 ◽  
pp. 101-106 ◽  
Author(s):  
Sergey V. Konovalov ◽  
V.E. Kormyshev ◽  
Yu.F. Ivanov ◽  
V.E. Gromov ◽  
I.A. Komissarova

The paper reports electro-contact welding on Hardox 450 steel with С-V-Cr-Nb-W flux-cored wire. Supplementary irradiation by intense pulsed electron beam was carried out to improve mechanical properties. Micro-and nanohardness, Young modulus and tribological parameters of the modified surface were tested mechanically. It is pointed at the significant increase in the friction coefficient because the surface layer fractures and particles of the surfaced layer are involved in the process of friction. Using the methods of optical and scanning microscopy a great number of micro-pores were detected both on the irradiated surface and through the surfaced layer modified by intense pulsed electron beam. It is demonstrated that electron-beam processing of the deposited layer surface is the reason for occurrence of multi-layer structure. According to measurements it was determined that the modified (surface and transition) layers are 0.3 to 0.5 μm on overage. It was also found out that irradiation of the surfaced metal leads to significant refining of structural elements because of ultrahigh speeds of crystallization and further cooling down of the modified layer. The phase composition of the surfaced metal modified by pulsed electron beam is explored. Niobium carbide (NbC) is reported to form in the surface layer.

2009 ◽  
Vol 79-82 ◽  
pp. 317-320
Author(s):  
Hui Zou ◽  
H.R. Jing ◽  
Sheng Zhi Hao ◽  
Chuang Dong

When high current pulsed electron beam (HCPEB) transferring its energy into a very thin surface layer within a short pulse time, super fast processes such as heating, melting, evaporation and consequent solidification, as well as dynamic stress induced may impart the surface layer with improved properties. In this paper, HCPEB modification of 45# carbon steel with working parameters of electron energy 25 kV, pulse duration 3.5µs, and energy density 4 J/cm2 was investigated. The microstructures of modified surface were analyzed by scanning electron microscope (SEM) of type JSM 5310 and transmission electron microscope (TEM) of type H-800. It is found that the modified surface layer can be divided into three zones: the white layer or melted layer of depth 3 to10µm, the heat and stress effecting zone 10 µm below and about 250 µm, then matrix, where a nanostructure and/or amorphous layer formed in the near-surface region. It is proved that the whole treatment process is not complex and cost-effective, and has a substantial potential to be applied in industries.


2013 ◽  
Vol 302 ◽  
pp. 66-71 ◽  
Author(s):  
N.S. Pushilina ◽  
Ekaterina N. Stepanova ◽  
E.V. Berezneeva ◽  
A.M. Lider ◽  
Ivan P. Chernov ◽  
...  

The paper presents the results of the pulsed beam effect on the structure and phase composition of zirconium alloy. Such treatment is demonstrated to lead to forming of complex morphology martensite in the surface layer of the alloy. The processes of hydrogen absorption by zirconium alloy with modified surface have been studied. Modification of the samples is found to reduce the amount of hydrogen, absorbed by the volume of zirconium alloy during hydrogenation.


2011 ◽  
Vol 675-677 ◽  
pp. 693-696 ◽  
Author(s):  
Y. Hao ◽  
Bo Gao ◽  
Gan Feng Tu ◽  
Z. Wang ◽  
Sheng Zhi Hao

The paper reports an analysis of the effect of high current pulsed electron beam(HCPEB) on microstructure transformations and wear resistance of hypereutectic Al-Si alloys. HCPEB treatment with 2.5 J /cm2 energy density leads to the formation of “halo” centered on primary Si, composition homogeneity, the formation of supersaturated solid solution of Al and grain refinement of top melted surface layer. The wear resistance of 15 pulse-treated Al-17.5Si and Al-20Si alloys is drastically improved by a factor of 6.5 and 2, respectively. The increase of hardness in modified surface layer has a positive effect on wear of hypereutectic Al-Si alloys.


2016 ◽  
Vol 683 ◽  
pp. 95-99 ◽  
Author(s):  
Victor Burdovitsin ◽  
Andrey Kazakov ◽  
Alexandr Medovnik ◽  
Efim Oks ◽  
Irina Puhova ◽  
...  

Influence of electron beam irradiation on the morphology and contact angle of polypropylene was investigated. Electron beam processing was carried out at 8 – 10 kV accelerating voltage and a pressure of 5 – 10 Pa. Beam current density was up to 4.5 A/cm2, and the pulse duration - from 150 to 300 μs. The morphology of irradiated polymer material was studied by scanning-electron and atomic-force microscopy methods. It was established formation of extended equally oriented “hills” divided by “valleys”. The height of hills increases with the growth of energy flux density per pulse.


1984 ◽  
Vol 35 ◽  
Author(s):  
M.S. Doghmane ◽  
D. Barbier ◽  
A. Laugier

ABSTRACTAu/Si Schottky contacts have been used as test structures to investigate defects induced in virgin C.Z (100) N-type silicon after irradiation with a 12 to 20 KeV mean energy electron beam pulse. A thin and highly damaged surface layer was observed from a fluence threshold of 1 J/cm2. In addition electron traps were detected in the PEBA induced melting layer with concentrations in the 1012-1013 cm-3 range. Their depth profiles have been related to the PEBA induced melting layer thickness. Quenching of multidefect complexes is the most probable mechanism for electron trap generation in the processed layer.


Author(s):  
Yu. F. Ivanov ◽  
O. L. Khasanov ◽  
M. S. Petyukevich ◽  
V. V. Polisadova ◽  
Z. G. Bikbaeva ◽  
...  

The elemental constituents, phase composition and substructural evolution were investigated in the article in the silicon carbide ceramics surface layer which was subjected to the intense pulsed electron beam the density of the electron beam being varied. It was shown that the ceramic layer surface's structure and phase conditions were controlled by the electron beam characteristics. The SiC-ceramics surface layer nanostructuring was detected and the electron beam treatment conditions which lead to this effect were defined.


2003 ◽  
Vol 21 (6) ◽  
pp. 1934-1938 ◽  
Author(s):  
Ying Qin ◽  
Chuang Dong ◽  
Xiaogang Wang ◽  
Shengzhi Hao ◽  
Aimin Wu ◽  
...  

2016 ◽  
Vol 35 (7) ◽  
pp. 715-721
Author(s):  
Jike Lyu ◽  
Bo Gao ◽  
Liang Hu ◽  
Shuaidan Lu ◽  
Ganfeng Tu

AbstractIn this paper, the effects of high current pulsed electron beam (HCPEB) on the microstructure evolution of casting HPb59-1 (Cu 57.1 mass%, Pb 1.7 mass% and Zn balance) alloy were investigated. The results showed a “wavy” surface which was formed with Pb element existing in the forms of stacking block and microparticles on the top surface layer after treatment. Nanocrystalline structures including Pb grains and two phases (α and β) were formed on the top remelted layer and their sizes were all less than 100 nm. The disordered β phase was generated in the surface layer after HCPEB treatment, which is beneficial for the improvement of surface properties. Meanwhile, there was a large residual stress on the alloy surface, along with the appearance of microcracks, and the preferred orientations of grains also changed.


2005 ◽  
Vol 475-479 ◽  
pp. 3959-3962 ◽  
Author(s):  
Sheng Zhi Hao ◽  
B. Gao ◽  
Ai Min Wu ◽  
Jian Xin Zou ◽  
Ying Qin ◽  
...  

High current pulsed electron beam (HCPEB) is now becoming a promising energetic source for the surface treatment of materials. When the concentrated electron flux transferring its energy into a very thin surface layer within a short pulse time, superfast processes such as heating, melting, evaporation and consequent solidification, as well as dynamic stress field induced by an abrupt thermal distribution in the interactive zone impart surface layer with improved physicochemical and mechanical properties. The present paper reports mainly our experimental research work on this new-style technique. Investigations performed with a variety of constructional materials (aluminum, carbon and mold steel, magnesium alloys) have shown that the most pronounced changes of composition, microstructure and properties occur in the near-surface layers, while the thickness of the modified layer with improved mechanical properties (several hundreds of micrometers) is significantly greater than that of the heat-affected zone due to the propagation of stress wave. The surfaces treated with either simply several pulses of bombardment or complex techniques, such as rapid alloying by HCPEB can exhibit improved mechanical and physicochemical properties to some extent.


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