Enhancement of Electric/Magnetic Field on NiAl Alloys

brothersroocooElectronics - Devices

Oct 18, 2013 (4 years and 21 days ago)

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Enhancement of Electric/Magnetic Field on NiAl Alloys

Dr.
C
hengwei

Wu
,
Professor, State Key Lab. Of Structural Analysis for Industrial
Equipment

Department of Engineering Mechanics

Dalian University of Technology
,
Dalian 116024, China


In the past decade,
electric and magnetic fields are often used to improve the
mechanical properties of metals and alloys

[1,2]. More and more new material
processing technologies are developed using electric or magnetic fields. It is found
that materials treated under high e
lectric/magnetic fields gave rise to either a high
strength or high
plasticity

by reducing the grain size or aligning the grains.



NiAl alloys show high hardness, high pressed strength and high wear
-
resistance. But
the alloys are very brittle and show a l
ow tensile strength, especially at room
temperature. Many methods are developed to improve the alloy ductility

[3
-
5] during
the past 10 years.


The current work in Dr. Wu

s group is to enhance the strength and ductile of NiAl
alloys and other materials usi
ng electric/magnetic fields. We have obtained a China
patent in this area. But most of the important results are not published so far. This
group now consists of one professor, one associate
professor
, one Ph.D student and
two graduate students. The main t
est equipments
available

are MTS materials testing
system, high voltage generator (0

50kV), one high magnetic field generator (<10T),
etc.


Objectives

(a)

How to safely use the high voltage generator and the high magnetic field
generator

(b)

How to use the MTS sy
stem

(c)

Enhancement mechanisms of high electric/magnetic field on mechanical
properties of materials


References

[1] Conrad H, Influence of an electric or magnetic field on the liquid
-
solid
transformation in materials and on the microstructure of the solid,
Mater. Sci. & Eng.
A287 (2000) 205
-
212

[2] Garnier M, Technological and economical challenges facing EMP in next century,
The 3rd Int. Symp. EPM, Nagoya, 2000, pp.3
-
8

[3] Zhow W L, Guo J T, et al, The deformation behavior of NiAlCrMoHf alloys under
high te
mperature, Rare Metals, 26 (2) (2002) 81
-
86 (in Chinese)

[4] Chen X F, et al, Deformation and fracture of a directional solidified
NiAl
-
28Cr
-
6Mo eutectic alloy, J. Mater. Res., 10 (1995) 1159
-
1470

[5] Heradia F E, et al, The fracture resistance of directio
nally solidified dual
-
phase
NiAl reinforced with refractory metals, Acta Mater., 41 (1993) 505
-
511