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| The relationship between deformation mechanism and porosity performance of metal fiber felt |
| HOU Liqiang，LUWenjing，LU Xiaofeng，ZHANG Xiaoqing |
| Xi’an Filter Metal Materials Co，Ltd，Xi’an 710201，China |
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Abstract In order to explore the effects of different strain variables on the pore characteristics of metal fiber felt,
the relationship between deformation mechanism and pore performance of metal fiber felt were analyzed. Using
stainless steel fiber with diameter of 6 μm and 22 μm as raw material, metal fiber felt of certain thickness was sintered
at high temperature through stacking, the changes of strain, porosity, air permeability, first bubble point pressure
and compression ratio of fiber layer were tested under the compressive strength of 5,10, 15, 20, 30 and
40 MPa.The results show that the ability of fiber felt to resist compression deformation increases with the increase
of strain, and the compression curve can be divided into two stages: weak deformation strengthening and strong
deformation strengthening. The resistance of 22 μm fiber layers to initial deformation are less than 6 μm fiber layers.
In the initial compression strain stage, the porosity and the pore diameter of compound ((6+22) μm) fiber felt
decrease slowly, the resistance to gas and bubble point pressure have little scope to rise, suggesting that the compression
strain has little impact on the filtration performance. However, when the compression strain exceeds 40%,
the porosity of fiber felt decreases obviously and the trend of gas permeability and bubble point pressure intensifies,
which has a serious impact on the filtration effect. Comparing the thickness changes of 6 μm and 22 μm fiber
layers during compression, it can be seen that in the original metal fiber felt structure, 22 μm fiber layers have
much larger pores than 6 μm fiber layers, performing the weak deformation resistance and low compression stress
and becoming the main part of the initial deformation. With the increase of compression stress, 22 μm fiber layers
are densified rapidly and the part bearing the overall deformation change to 6 μm fiber layers, then the pore change
becomes a greater impact on the filtration performance. Until the deformation reaches the limit, it turns to 22 μm fiber
to bear the deformation again. The whole deformation shows the alternate deformation mechanism of the
coarse is fiber layers - the fine fiber layers - the coarse fiber layers.
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Received: 20 February 2021
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2022, Vol. 32 
