| Title |
Effect of Strain Rate & Temperature on the Yield Stress Anomaly in β-CuZn alloy |
| Authors |
이기안(Kee Ahn Lee); 장영원(Young Won Chang); 이종수(Chong Soo Lee) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Yield stress anomaly; β-CuZn alloy; Strain rate dependence; Vacancy hardening; Load relaxation test |
| Abstract |
A series of tensile and load relaxation behaviors in B2 type β-CuZn alloy have been examined to clarify the strain rate & the temperature dependence of yield stress anomaly. It has been found in tensile tests that the region showing anomalous peak of yield stress moves to a higher stress and higher temperature region with increasing strain rate. The anomalous yielding region below peak temperature(T_p) revealed slightly positive strain rate dependence, while the region above T_p showed considerably positive strain rate dependence. The slip lines formed below peak temperatures (T_P) were clearly visible with naked eye(coarse slip lines), and became finer near T_p(fine slip lines), while they disappeared completely above T_p. Based on the different tendency of temperature and strain rate dependence of anomalous yielding as the above-mentioned results, two types of deformation modes were suggested and incorporated into the flow curve analysis, which was in accord well with the experimental results. The slightly positive strain rate dependence of yield stress anomaly indicated that the yield stress anomaly in β-CuZn alloy mainly seemed to be attributed to the vacancy hardening. |