X.H. You
,
Q.L. Zhang and H.G. Guo Taiyuan Heavy Machinery Institute
,
Taiyuan 030024
,
China
金属学报(英文版)
The significance of this paper lies in the application of bending-upsetting 35CrMo steel in train crack-shaft. The hot deforming tests of 35CrMo steel have been done on the Gleeble-1500 testing machine with the deformation temperature at the range of 900癈-1250癈, a strain strain of 0.05 s-1, 0.5 s-1, 1.0 s-1 and compress degree of 15%-80%. Through respectively analyzing and studying the microstructure of the specimen and getting the data from the testing, the results obtained are as follows: the model of flow stress and the stress-strain relationship of material hot deformation, the model of dynamic and static re-crystallization and the correlative references of hot forming parameters and changes of microstructure. The hot deforming stress-strain curses and relevantly re-crystallized micro-structure of 35CrMo steel are drawn at the deformation temperature of 1250 and the strain rate of 1.0 s. Through analyzing and regressive calculating the grain size of the deformation specimen of 35CrMo steel at different locations under the large-deformation and high-temperature conditions, the hot-deforming model of grain calculation is verified. The experimental results and the model of grain calculation can provide scientific basis for analyzing the hot deformation processes and controlling quality.
关键词:
35CrMo steel
,
null
,
null
X.H. You
,
F. Wang
,
L.C. Wang
金属学报(英文版)
A new technique, powder compact foaming process for the production of aluminum
foams has been studied in this article. According to this method, the aluminum powder is mixed with a powder foaming agent (TiH2). Subsequent to mixing, the powder
blend is hot compacted to obtain a dense semi-finished product. Upon heating to temperatures within the range of the melting point, the foaming agent decomposes to evolve
gas and the semi-finished product expands into a porous cellular aluminum. Foaming
process is the key in this method. Based on experiments, the foaming characteris-
tics were mainly analyzed and discussed. Experiments show that the aluminum-foam
with closed pores and a uniform cell structure of high porosity can be obtained using
this method by adjusting the foaming parameters: the content of foaming agent and
foaming temperature.
关键词:
aluminum foams
,
null
,
null
