scholarly journals Study on microstructure and wear resistance of Zr-17Nb alloy irradiated by high current pulsed electron beam

2020 ◽  
Vol 59 (1) ◽  
pp. 514-522
Author(s):  
Yue Sun ◽  
Kui Li ◽  
Bo Gao ◽  
Pengyue Sun ◽  
Haiyang Fu ◽  
...  

AbstractIn this paper, the microstructure and wear resistance of Zr-17Nb alloy treated by high current pulsed electron beam were studied in detail. A phase change occurs after pulse treatments using X-Ray Diffraction (XRD) analysis, showing β (Nb) phase and α (Zr) phase transformed by a part of β (Zr, Nb) phase. Also, narrowing and shifting of β (Zr, Nb) diffraction peaks were found. Scanning Electron Microscope (SEM) and metallographic analysis results reveal that the microstructure of alloy surface before high current pulsed electron beam (HCPEB) treatment is composed of equiaxed crystals. But, after 15 and 30 pulse treatments, crater structures are significantly reduced. Besides, it was also found that the alloy surface has undergone eutectoid transformation after 30 pulse treatments, and the reaction of β (Zr, Nb) → αZr + βNb had occurred. Microhardness test results show that microhardness value presents a downward trend as the number of pulses increases, which is mainly due to the coarsening of the grains and the formation of a softer β (Nb) phase after phase transformation. The wear resistance test results show that the friction coefficient increases first, then decreases and then increases with the increase of pulse number.

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
L. Hu ◽  
B. Gao ◽  
J. K. Lv ◽  
S. C. Sun ◽  
Y. Hao ◽  
...  

Halo evolution of an Al-17.5Si alloy surface after treatment with increasing pulse numbers of a high-current pulsed electron beam (HCPEB) was investigated. A halo is a ring microstructure resembling a bull’s eye. SEM results indicate that the nanocrystallization of halo induced by HCPEB treatment leads to gradual diffusion of the Si phase. Multiple pulses numbers cause the Si phase to be significantly refined and uniformly distributed. In addition, nanosilicon particles with a grain size of 30~100 nm were formed after HCPEB treatment, as shown by TEM observation. XRD results indicate that Si diffraction peaks broadened after HCPEB treatment. The microhardness tests demonstrate that the microhardness at the midpoint from the halo edge to center decreased sharply from 9770.7 MPa at 5 pulses to 2664.14 MPa at 25 pulses. The relative wear resistance of a 15-pulse sample is effectively improved by a factor of 6.5, exhibiting optimal wear resistance.


2013 ◽  
Vol 423-426 ◽  
pp. 276-280
Author(s):  
Hui Hui Wang ◽  
Sheng Zhi Hao

High current pulsed electron beam (HCPEB) treatment was conducted on 40CrNiMo7 steel. The surface microstructure was characterized by metalloscopy and X-ray diffraction methods. The microhardness and wear resistance of modified surface were measured. After the HCPEB treatment, the surface crater structure was observed due to the inhomogeneity of initial material. A modified layer of depth ~ 7 μm was formed with a hybrid microstructure composed mainly of martensite and a small quantity of austenite. The surface microhardness of HCPEB modified sample was increased drastically to more than 1000 HK. The wear resistance increased by about 36% as compared to the initial state.


2011 ◽  
Vol 299-300 ◽  
pp. 77-81
Author(s):  
Yang Xu ◽  
Sheng Zhi Hao ◽  
Xiang Dong Zhang ◽  
Min Cai Li ◽  
Chuang Dong

The surface irradiation of 6063 aluminum alloy by high current pulsed electron was conducted with the aim of replacing the complicated pre-treatment in the processes of electroless plating. To explore the microstructure changes, optical metallography, SEM (scanning electron microscope), XRD (X-ray diffraction) analyses were carried out, and the sliding tests were used for the detection of wear resistance. It was concluded that the HCPEB irradiation could replace the pre-treatment of aluminum substrate as required in conventional electroless plating with a decreased surface roughness of Ni-P alloy plating layer. The plates exhibited an amorphous microstructure as demonstrated by XRD analysis. The plates, produced with the routine of HCPEB irradiation, activation and electroless plating possess, also exhibited good quality, even better than that of conventional electroless plating technique.


2010 ◽  
Vol 154-155 ◽  
pp. 1170-1177
Author(s):  
Yuan Fang Chen ◽  
Xiao Dong Peng ◽  
Jian Jun Hu ◽  
Hong Bin Xu ◽  
Chan Hao

Surface modification of 40Cr steel by high current pulsed electron beam has been investigated . The pulsed times of HCPEB was changed from 1 to 25 to prepare different specimens. Surface microstructures and section microstructures after HCPEB irradiation were detected by using metallurgical microscope, SEM and X-ray diffractometer. It is shown that crater defects were found on the surface after the irradiation of HCPEB and the density of craters will decrease with increasing pulses times. When treated by 27Kev accelerating voltage, with increasing pulse times, the particles located in surface layer were obviously refined .The surface roughness, hardness, wear properties and corrosion resistance were analyzed after irradiation of HCPEB. The wear resistance and corrosion resistance were obviously enhanced after 10 pulses treatment.


2011 ◽  
Vol 189-193 ◽  
pp. 1204-1207 ◽  
Author(s):  
Bo Gao ◽  
Yi Hao ◽  
Gan Feng Tu ◽  
Shi Wei Li ◽  
Sheng Zhi Hao ◽  
...  

High current pulsed electron beam (HCPEB), a novel high-power energetic beam technology, has been developed as a useful tool for surface modification of materials. In the present work, the effect of HCPEB treatment on microstructure and wear resistance of Al-15Si and ZK60-1Y Mg alloys was investigated. The results show that a supersaturated solid solution of (Al) and (Mg) is formed on top surface of melted layer induced by rapid heating and cooling during HCPEB process. In addition, the melted layer of approximately 5~11μm thickness is obtained on the ZK60-1Y Mg alloy surface. Wear resistance of Al-15Si and ZK60-1Y Mg alloys are significantly improved after HCPEB treatment. It is demonstrated that HCPEB technology has a good application future in enhancing surface properties of Al-Si and Mg alloys.


Nanomaterials ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 74 ◽  
Author(s):  
Lingyan Zhang ◽  
Ching-Tun Peng ◽  
Jintong Guan ◽  
Peng Lv ◽  
Qingfeng Guan ◽  
...  

In this investigation, chromium (Cr) was adopted as an alloying element on a nickel substrate, and the alloying process was materialized via high-current pulsed electron beam (HCPEB) irradiation. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were also conducted for microstructure characterization. The results showed that after HCPEB irradiation a nanocrystalline Cr-Ni alloying layer was formed and numerous dislocations were generated, resulting in a great deal of diffusion paths for Cr elements. Moreover, properties including hardness, wear and electrochemical performance were significantly improved after HCPEB irradiation, which was mainly due to the formation of the nanocrystalline Cr–Ni alloying layer. In addition, each strengthening mechanism that contributed to the hardness of the HCPEB-irradiated sample was mathematically analyzed, and solid solution strengthening was found to be of great importance.


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