A Quantitative Electron Microscopic Examination of Nb-and V(C,N) Precipitates in Eutectoid, Premium Rail Steels Transformed Under Various Conditions
| Autor: | E. E. Laufer, D. M. Fegredo |
|---|---|
| Rok vydání: | 1983 |
| Předmět: | |
| Zdroj: | Canadian Metallurgical Quarterly. 22:193-203 |
| ISSN: | 1879-1395 0008-4433 |
| DOI: | 10.1179/cmq.1983.22.2.193 |
| Popis: | Experimental eutectoid rail steels with various thermal histories and containing Nb and/or V were examined by TEM to characterize precipitate size and distribution and to determine pearlite interlamellar spacing. Existing equations were used to calculate the sum of the increments of strengthening by precipitates and by the interlamellar spacing and composition of the pearlite. The results were compared with measured or estimated values of yield strength. Wide differences were observed for steels with very small interlamellar spacings implying the possibility that other strengthening mechanisms, e.g. dislocation strengthening, are significant, or that the Hall–Petch equation does not strictly apply for these spacings. A plot of the data indicates that (i) alternative Hall–Petch coefficients apply and (ii) additions of ∼ 0.1 % V can play a major role in increasing the hardness by ∼ 5 Rc points or the yield strength by ∼ 200 MPa, whereas that the effect of niobium seems limited. Resume Plusieurs acie... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|