Fatigue damage is the most common kind of failure for metal materials. Traditional non-destructive testing (NDT) methods fail to predict early fatigue damage. Magnetic Metal Memory (MMM) Testing, a new NDT technology, has the potential of fatigue damage evaluation. This paper aims to investigate fatigue mechanical property of ferromagnetic material with the MMM method. Steel Q235 samples with different depth and breadth artificial crack are tested in rotary bending fatigue machinery. The MMM fatigue features are as follows: the tangent component Hp(x) of magnetic induction intensity is gradually increasing up to the peak value while the fatigue crack is initiating and growing; after that peak, Hp(x) is descending with the crack deepening. Furthermore, the features have been studied theoretically.

1.
Dubov
A. A.
Study of metal properties using metal magnetic memory method [A]. 7th European Conference on Non-destructive Testing [C]
.
Copenhagen
.
1997
, (
10)
:
920
927
.
2.
Doubov, A.A. Diagnostics of metal items and equipment by means of metal magnetic memory [A]. ChS NDT 7th Conference on NDT and International Research Symposium [C]. Shantou China, 1999: 181–187.
3.
Doubov
A. A.
A technique for monitoring the bends of boiler and steam-line tubes using the magnetic memory of metal [J]
.
Thermal Engineering.
2001,
48
(
4)
:
289
295
.
4.
Dubov
A. A.
Problems in estimating the remaining life of aging equipment [J]
.
Thermal Engineering.
2003
,
50
(
11)
:
935
938
.
5.
Dong
Lihong
,
Xu
Binshi
,
Dong
Shiyun
.
Metal magnetic memory testing for early damage assessment in ferromagnetic materials[J]
.
J. CENT. SOUTH UNIV. TECHNOL.
2005
,
12
(
S2)
:
102
106
This content is only available via PDF.
You do not currently have access to this content.