不同调制波长Cu/Ag多层膜硬度分析

用直流电沉积双槽法在纯铜基体上制备了不同调制波长的Cu/Ag多层膜,研究了多层膜硬度与调制波长之间的关系.实验结果表明,当调制波长位于600～300nm时,Cu/Ag多层膜的硬度与调制波长之间较好地符合基于位错塞积模型的Hall-Petch关系;当调制波长小于300 nm时,硬度与调制波长的关系偏离了HaU-Petch关系.由实验结果分析得出了Cu/Ag多层膜的位错稳定存在极限晶粒尺寸约为25 nm,与基于程开甲等人的位错稳定性理论得出的Ag晶体极限晶粒尺寸27 nm接近,验证了程开甲等人的位错稳定性理论.

Analysis of the Hardness for Cu/Ag Multilayers with Various Modulation Wavelengths

Cu/Ag multilayers with various modulation wavelengths were deposited on pure Cu substrates by the double-cell electrodeposition process.The relationship between the hardness of multilayers and their modulation wavelengths was studied.The results show that the relationship could be described by the Hall-Petch relation based on dislocation pile-up when the modulation wavelengths are in the regime of 300-600 nm,and the Hall-Petch relation breaks down when the modulation wavelength is below 300 nm.The limit size of the grains with stable dislocations for Cu/Ag multilayers,which is obtained by analyzing experimental results,is about 25 nm.Based on the theory of dislocation stability proposed by Cheng et al.,the limit grain size of Ag crystal with stable dislocation is 27 nm.The theoretical value is close to the experimental value.It is better to demonstrate the theory.