Portevin-Le Chatelier (PLC) effect in a severely cold-rolled Al-Zn-Mg-Cu-Zr aluminum alloy (AA7055 type) plate before and after annealing was investigated. The results show that the sample annealed at 300 ℃ undergoes...Portevin-Le Chatelier (PLC) effect in a severely cold-rolled Al-Zn-Mg-Cu-Zr aluminum alloy (AA7055 type) plate before and after annealing was investigated. The results show that the sample annealed at 300 ℃ undergoes PLC effect,whereas the PLC effect is not observed in the deformed sample or the samples annealed at 110 ℃ or 200 ℃. The main precipitates in the sample annealed at 300 ℃ are the coarsened η phases,while a mixture of small η' phases and η phases dominates in the sample annealed at 200 ℃. In the deformed sample and sample annealed at 110 ℃,GP zone are the main precipitates. The different flow behaviors are ascribed to the type of precipitates as well as the dislocation density differences.展开更多
基金Project(2005CB23705) supported by the National Basic Research Program of China
文摘Portevin-Le Chatelier (PLC) effect in a severely cold-rolled Al-Zn-Mg-Cu-Zr aluminum alloy (AA7055 type) plate before and after annealing was investigated. The results show that the sample annealed at 300 ℃ undergoes PLC effect,whereas the PLC effect is not observed in the deformed sample or the samples annealed at 110 ℃ or 200 ℃. The main precipitates in the sample annealed at 300 ℃ are the coarsened η phases,while a mixture of small η' phases and η phases dominates in the sample annealed at 200 ℃. In the deformed sample and sample annealed at 110 ℃,GP zone are the main precipitates. The different flow behaviors are ascribed to the type of precipitates as well as the dislocation density differences.