Y.L. Yang
,
C.S. Liu
,
F.J. Sun
,
D. Zhang
金属学报(英文版)
CW-CO2 laser nitriding technique was applied to improve the properties (such as aging property and the core loss) of grain oriented silicon steel. The samples were nitrided with regular space. Laser power density and scanning speed were chosen as 7.8×105W·cm-2 and 100mm·min-1. By some laser irradiation, Fe4N and Fe3N were formed in the nitrided zone. The nitrided samples were annealed at the temperatures ranged from 100 to 900°C. The core loss of some interested samples was tested. The results show that the core loss of the nitrided samples with different thickness of 0.23 and 0.30mm decreased by 14.9% and 9.4% respectively, and the aging property were improved up to 800°C. The mechanism of laser nitriding to improve the properties of grain oriented silicon steel is discussed.
关键词:
laser nitriding
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null
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null
Y.G. Wang
,
Z.Q. Li
,
D. Zhang
金属学报(英文版)
The interfacial microstructure of ternary-boride-based hard cladding material (YF- 2) has been studied using scanning electron microanalyser (SEM), X-ray diffraction (XRD) and energy disperse spectroscopy (EDS). Results show that there are chemical reactions and elements diffusion in the interfacial zone, which make the interface bonding well and bonding strength ideal at the interface. The results gotten by studying of crack produced by Vickers indentation technique in the interfacial zone show that it is diffcult to produce crack in the interface, the crack length in the cladding layer is longer than that to the interface, the crack which propagate to the interface stops at the interface rather than propagates along the interface. This suggests negligible residual stresses have developed because of thermal expansion mismatch. The bonding strength of the interface is 550MPa, which has been gotten by cutting test. The result gotten by analyzing the fracture surface shows that the fracture occurs at the side of cladding layer, which conrms that the bonding strength at the interface is higher than that in the cladding layer.
关键词:
ternary boride
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null
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