Y.D. Yu
,
K.F. Zhang
,
H.R. Zheng
,
D.M. Jiang
金属学报(英文版)
Numerical simulation and experimental studies on cavity growth were carried out during the bulging process of superplastic magnesium Alloy. A three-dimensional rigid-
viscoplastic finite element program has been developed and applied to predict the cavity radiusand volume fraction of cavity growth. The final prediction on the cavity
radius and volume fraction distribution was exhibited as colorful shade pictures. The
experimental studies wereperformed under similar conditions to the numerical one
and provided for quantitativecomparison. According to the metallography observation,
the radius and volume fraction of cavity growth was quantitative achieved by using
Profound-Iron & steel software. The numerical results were in reasonable quantitative agreement with the experiment.
关键词:
magnesium alloy
,
null
,
null
,
null
W.B. Han
,
K.F. Zhang
,
B. Wang
,
D.Z. Wu
金属学报(英文版)
The superplasticity and diffusion bonding of IN718 superalloy were studied in this article. The strain rate sensitivity index m was obtained at different temperatures and various initial strain rates using the tensile speed mutation method; m reached its maximum value 0.53 at an initial strain rate of 1×10-4s-1 at 1253K. The diffusion bonding parameters, including the bonding temperature T, pressure p, and time t, affected the mechanism of joints. When the bonded specimen with 25μm thick nickel foil interlayer was tensile at room temperature, the shear fracture of the joints with nickel foil interlayer took place at the IN718 part. Microstructure study was carried out with the bonded samples. The microstructure shows an excellent bonding at the interfaces. The optimum parameters for the diffusion bonding are: T = 1273-1323K, p = 20-30MPa, t = 45-60min.
关键词:
superplasticity
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null
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null
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