( 西安交通大學(xué) 金屬材料強(qiáng)度國(guó)家重點(diǎn)實(shí)驗(yàn)室，
西安 710049)
摘 要: 在JGP560V磁控濺射鍍膜設(shè)備上鍍制多晶銅膜，利用納米壓入技術(shù)測(cè)量了其室溫下的蠕變性能。 結(jié)果表明： 由于不同加載方式下， 材料加工硬化程度的不同造成了應(yīng)力指數(shù)的差異， 因而， 不同加載方式對(duì)測(cè)得的銅膜蠕變應(yīng)力指數(shù)有比較大的影響；由于材料在高載荷時(shí)在壓頭下端產(chǎn)生更多的位錯(cuò)， 阻礙了壓頭的壓入， 使蠕變率降低， 因而， 隨著保載載荷的升高， 蠕變應(yīng)力指數(shù)變大。
關(guān)鍵字: 納米壓入; 蠕變; 殘余應(yīng)力; 應(yīng)力指數(shù)
（ State Key Laboratory for Mechanical Behavior of Materials,Xi′an Jiaotong University, Xi′an 710049, China）
Abstract: Two creep experiments were conducted on polycrystalline Cu thin films with nanoindentation instrument. The thin films were deposited by magnetron sputtering technique. The results show that the loading modes have great effect on the nanoindentation creep properties. The changes of stress exponent depend on the rate of work hardening under different loading conditions. And with increasing holding load, the stress exponents increase under both two loading modes because of many accumulated dislocations under the indenter tip, which reduces the creep rate for the indenter and makes it difficult to penetrate further.
Key words: nanoindentation; creep; residual stress; stress exponent
