Sinterizazio-atmosferaren eragina M graduko (ASP 30 ... - Euskara

CONCLUSIONS
1 . Addition of free carbon causes a reduction in the optimum sintering
temperature in both steels for vacuum and gas atmosphere sintering .
2 . Sintering in the gas atmosphere produces a nitrogenation of both steels,
being the nitrogen content higher in Px30 than in Px30S .
3 . Sintering in the gas atmosphere rich in nitrogen produces also a decreasing
of the optimum sintering temperature in both steels, showing a clear effect
also in M grade steels .
4 . The increase in nitrogen content of both steels during gas atmosphere
sintering has no effect in the chemical composition of M 6C carbides, but
transforms the MC carbides found in vacuum sintering to MX carbonitrides .
5 Densification at lower temperatures during industrial atmosphere sintering
seems to be related with the transformation of VC carbides to VX
carbonitrides leaving carbon free . This free carbon reduces -the solidus
temperature and in consequecence the optimum sintering temperature .
When sintering in- - the --atmosphere, important oversint -erings---coo - not
significantly modify the microstructure, and do not produce a continuous film
of eutectic phase . This will allow a large sintering range to be employed when
sintering in atmosphere, and additional advantage to be added to the
possibility of continuous sintering that would allow atmosphere sintering .
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