Abstract
Cold working is well known to be a very effective process to strengthen austenitic stainless steels. Due to their low stacking fault energy nitrogen alloyed austenitic stainless steels exhibit an unusual high work hardening capacity. This paper discusses mechanical and structural properties of cold and warm worked austenitic steels. It is shown that work hardening at elevated temperatures is comparable to work hardening performed at room temperature. However, the forces necessary for the equivalent plastic deformation are much smaller in the case of warm working. This fact is illustrated with flow stress data between room temperature and 600 °C for a nitrogen alloyed CrMn-steel. Furthermore, this paper presents results of tensile tests conducted on different alloys which were previously cold worked to different strength levels. It is found that the strain hardening rate decreases strongly with increasing cold deformation. At very high degrees of deformation no strain hardening is observed and sometimes even strain softening takes place. This behavior is explained by the inhomogeneous development of the microstructure. At high strains most of the deformation is carried by shear bands.
Original language | English |
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Pages | 603-608 |
Number of pages | 6 |
Volume | 86 |
No | 12 |
Specialist publication | Metallurgia Italiana |
State | Published - Dec 1994 |