CAJ | 학술논문

通过对不同结构的高纯钨进行微米和纳米压痕实验，发现压痕尺寸和晶粒/亚晶粒尺寸对材料的硬度有重要影响。探讨硬度的晶界效应和压痕尺寸效应。采用Nix?Gao模型，结合尺度因子对实验获得的压痕硬度值进行拟合。结果表明，尺度因子几乎与晶粒或亚晶粒的尺寸无关。塑性变形区与晶界或亚晶界之间的相互作用是导致硬度在某一特定深度增加的原因，而塑性变形区与晶粒或亚晶粒的尺寸几乎无关。当塑性变形区扩展增大到单个晶粒或亚晶粒尺寸时，压痕硬度开始趋于稳定。
통과대불동결구적고순오진행미미화납미압흔실험，발현압흔척촌화정립/아정립척촌대재료적경도유중요영향。탐토경도적정계효응화압흔척촌효응。채용Nix?Gao모형，결합척도인자대실험획득적압흔경도치진행의합。결과표명，척도인자궤호여정립혹아정립적척촌무관。소성변형구여정계혹아정계지간적상호작용시도치경도재모일특정심도증가적원인，이소성변형구여정립혹아정립적척촌궤호무관。당소성변형구확전증대도단개정립혹아정립척촌시，압흔경도개시추우은정。
Hardness of materials depends significantly on the indentation size and grain/sub-grain size via microindentation and nanoindentation tests of high-purity tungsten with different structures. The grain boundary effect and indentation size effect were explored. The indentation hardness was fitted using the Nix?Gao model by considering the scaling factor. The results show that the scaling factor is barely correlated with the grain/sub-grain size. The interaction between the plastically deformed zone (PDZ) boundary and the grain/sub-grain boundary is believed to be the reason that leads to an increase of the measured hardness at the specific depths. Results also indicate that the area of the PDZ is barely correlated with the grain/sub-grain size, and the indentation hardness starts to stabilize once the PDZ expands to the dimension of an individual grain/sub-grain.