具有失稳分解转变的Al-Zn-(Cu)系合金的固溶强化与析出强化

通过组织观察、X射线衍射及硬度测定对AlZn(Cu)系合金的固溶强化和析出强化效应进行了研究·结果表明,合金的强化主要取决于溶质原子的固溶强化作用,而合金发生失稳分解所产生的时效硬化作用很弱·对于AlZn2Cu实验合金来说,其固溶强化效应约为1GPa,而析出强化效应约为180MPa·Cu原子的加入不仅提高了AlZn合金的组织稳定性,使合金失稳分解造成的硬化峰值的出现大大推迟,而且2%Cu原子的加入使合金的淬火硬度约提高300MPa·

Solution Strengthening and Precipitation Strengthening in Spinodally Decomposed Al-Zn-(Cu) Alloys

Microstructure evolution and accompanying hardness changes in spinodally decomposed Al Zn (Cu) alloys were studied by microstructure observation, X ray diffraction and hardness measurement. The results show that the strengthening of the alloys mainly comes from the solid solution of alloying atoms, and the precipitation strengthening caused by spinodal decomposition is much less effective. The hardness increment of the AlZn 2Cu alloy caused by solution strengthening is about 1?GPa. The peak HV hardness increment caused by spinodal decomposition in the same alloy is only about 180?MPa. Adding Cu atoms improves the stability of the microstructure in Al Zn alloy and greatly delays the aging time to reach the peak hardness state caused by spinodal decomposition. Adding 2% copper makes the hardness of the as quenched AlZn alloy be increased by 300?MPa.