Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9795831 | Materials Science and Engineering: A | 2005 | 9 Pages |
Abstract
The disappearing and forming behavior of B2 ordered phase in high Si steels with Si-levels between 5 and 6.5% (by weight, unless specified otherwise) was investigated by observing TEM and measuring electrical resistivity and micro- and nano-hardness. The critical cooling rate for suppressing the formation of B2 ordered phase increased exponentially with Si-content. The ordered phase coarsening was observed to occur actively above 800 °C, where atoms have enough mobility. The removal of solidification segregation is necessary in order to reduce the amount of B2 ordered phase in the as-cast or hot-rolled state, to lower the annealing temperature for the dissolution of B2 ordered phase, and to shorten the annealing time. Micro-Vickers hardness depended only on Si-content even under various heat treatment conditions, and the nano-hardness had a small difference between B2 and A2 phases. In the high Si steels, the short-range order in A2 disordered phase was likely to cause a comparable hardness as that of B2 ordered phase.
Related Topics
Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
J.S. Shin, J.S. Bae, H.J. Kim, H.M. Lee, T.D. Lee, E.J. Lavernia, Z.H. Lee,