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Studies of residual stress, microcracks, hardness and microstructure of cold compacted metallic green bodies

Published online by Cambridge University Press:  11 February 2011

Torsten Ericsson
Affiliation:
Linköping University, 581 83 Linköping, Sweden
Cecilia Larsson
Affiliation:
Linköping University, 581 83 Linköping, Sweden
Ru Lin Peng
Affiliation:
Linköping University, 581 83 Linköping, Sweden
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Abstract

The residual stresses have been measured by X-ray and neutron diffraction on PM green bodies manufactured by conventional and high speed compaction of iron powder with and without added copper and brass powder. Compressive residual stresses are present in a thin layer in both top and side surfaces. They are largest in the side surfaces due to plastic deformation of the surface material caused by the friction forces during ejection out of the die. In the interior of the green body residual stresses exist with certain region under compression (periferical regions) and other under tension (more central regions). It is unclear whether mixing iron powder with brass or copper powder leads to considerable phase stresses between the two phases.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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References

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