Y. Zhou
,
C.S. Yang
,
J.A. Chen
,
G.F. Ding
,
L. Wang
,
M.J. Wang
,
Y.M. Zhang
,
T.H. Zhang
金属学报(英文版)
Microbridge testing is used to measure the Young's modulus and residual stresses of
metallic films. Nickel film microbridges with widths of several hundred microns are
fabricated by Microelectromechanical Systems. In order to measure the mechanical
properties of nickel film microbridges, special shaft structure is designed to solve the
problem of getting the load-deflection curves of metal film microbridge by Nanoindenter XP system with normal Berkovich probe. Theoretical analysis of the microbridge load-deflection curve is proposed to evaluate the Young's modulus and residual
stress of the films simultaneously. The calculated results based on the experimental
measurements show that the average Young's modulus and residual stress are around
190GPa and 175MPa respectively, while the Young's modulus measured by Nano-
hardness method on nickel film with silicon substrate is 186.8±7.34GPa.
关键词:
nickel film microbridge
,
null
,
null
,
null
Z.W. Yu
,
L. Wang
,
X.L. Xu
,
J.B. Qiang
金属学报(英文版)
The growth process of low-temperature plasma-nitriding layer was investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The layer is composed
of expanded fcc phase (γN), whose lattice parameter of the layer increases with process
time resulting from increasing the nitrogen content. The layer hardness increases gradually with nitrogen content. The high slip band density on the layer surface observed
in situ by SEM shows that the surface yield occurs when supersaturated nitrogen content in the layer attains to some value, which is also responsible for the increase in
layer hardness.
关键词:
austenitic stainless steel
,
null
,
null
X.L. Xu
,
L. Wang
,
Z. W. Yu and Z.K. Hei(Institute of Metal and Technology
,
Dalian Maritime University
,
Dalian 116024
,
China)
金属学报(英文版)
The cross-sectional microstructure of an ion-nitrided layer on a No.45 steel was studied by transmission electron microscopy (TEM). The results show that the columnar crystals constitute the compound layer. Most of them have the microstructure of alternating ε-Fe2-3N and γ-Fe4N and others are single ε-Fe2-3N phase. There are abnormal strip ferrites between the columnar crystals. The transition layer mainly consists of spherical γ-Fe4N and cementite (Fe3C) particles in the pearlite are dissolved in this layer. In diffusion layer, besides the equilibrium phase γ-Fe4N, there are α -Fe16N2 and the satellite spots around main spots of α-Fe16N2 demonstrate its modulation structure. A metastable ordered cluster zone of the nitropen atoms was found in the division layer.
关键词:
ion nitriding
,
null
,
null
