| Autor: |
D. T. Scott, M.W. Woodmansee, Richard W. Neu |
| Rok vydání: |
2000 |
| Předmět: |
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| Zdroj: |
International Journal of Plasticity. 16:283-301 |
| ISSN: |
0749-6419 |
| Popis: |
Unified creep-plasticity models often require a number of internal state variables to accurately capture the path dependence of rate- and temperature-dependent alloys especially at intermediate to high homologous temperatures. However, it is impossible to fully measure the internal state variables directly. Consequently, assumptions on the relative importance of the various state variables must be made when determining the material parameters and their evolution must be inferred. Any enhancements designed to better capture the evolution of the state variables are dependent on these assumptions and are generally limited. The strain transient dip test and the rapid load/unload test are two indirect experimental methods used to obtain an approximate measure of the evolutionary nature of the back stress in 60Sn–40Pb, a common rate- and temperature-dependent solder alloy. The rapid load/unload test gives a better measure of back stress because there is less time for the internal state to evolve during data acquisition. Modifications to the back stress evolution equations in the McDowell unified creep-plasticity model are proposed using these new measurements as guidance. The modified model can better capture the transients under cyclic loading and following strain-rate jumps. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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