本文關(guān)鍵詞： 橋域法 定量化統(tǒng)計(jì) 納米摩擦 位錯(cuò)　出處：《功能材料》2017年09期 　論文類型：期刊論文

【摘要】：采用橋域方法(bridging domain method)對納米尺度下Cu薄膜表面摩擦過程進(jìn)行模擬,主要對不同壓頭壓入深度和摩擦速度下的模擬結(jié)果進(jìn)行對比分析。對摩擦阻力和系統(tǒng)變形能的對比分析表明,壓深增大使得摩擦阻力和變形能顯著增加,而摩擦速度增大對二者并無顯著影響;對位錯(cuò)原子數(shù)目的統(tǒng)計(jì)分析表明,壓深變化對摩擦過程中不全位錯(cuò)和全位錯(cuò)的發(fā)生具有明顯影響,表現(xiàn)為不全位錯(cuò)和全位錯(cuò)原子數(shù)目隨壓深增加而顯著增加;定量化分析位錯(cuò)、孿晶等不同變形機(jī)制對總應(yīng)變的貢獻(xiàn)比重表明,壓深變化對摩擦過程中不同變形機(jī)制的應(yīng)變貢獻(xiàn)影響有差異,主要表現(xiàn)為FCC原子應(yīng)變貢獻(xiàn)隨壓深增加而降低,位錯(cuò)、孿晶原子應(yīng)變貢獻(xiàn)受壓深變化影響較小。摩擦速度變化對摩擦過程中不全位錯(cuò)、全位錯(cuò)的發(fā)生以及不同變形機(jī)制的總應(yīng)變貢獻(xiàn)均無明顯影響,這與不同摩擦速度下摩擦阻力、變形能的分析結(jié)果一致。
[Abstract]:The surface friction process of Cu films at nanoscale was simulated by bridging domain method. The simulation results of different indentation depth and friction velocity are compared. The comparison of friction resistance and system deformation energy shows that the increase of pressure depth makes friction resistance and deformation energy increase significantly. However, the increase of friction velocity has no significant effect on them. The statistical analysis of the number of dislocation atoms shows that the variation of pressure depth has a significant effect on the occurrence of incomplete dislocation and total dislocation in the friction process, which shows that the number of incomplete dislocation and total dislocation atom increases significantly with the increase of pressure depth. Quantitative analysis of the contribution of different deformation mechanisms, such as dislocations and twins, to the total strain shows that the effect of the depth variation on the strain contribution of different deformation mechanisms in friction process is different. The results show that the strain contribution of FCC atom decreases with the increase of compression depth, while the dislocation and the strain contribution of twin atom are less affected by the variation of compression depth, and the variation of friction velocity has less effect on the incomplete dislocation in the friction process. The occurrence of total dislocation and the total strain contribution of different deformation mechanisms have no obvious influence, which is consistent with the analysis of friction resistance and deformation energy at different friction speeds.
【作者單位】： 復(fù)旦大學(xué)航空航天系;
【基金】：國家自然科學(xué)基金資助項(xiàng)目(11572090)
【分類號】：TB383.2;TG146.11
【正文快照】： 0引言隨著實(shí)驗(yàn)操作與工業(yè)生產(chǎn)的精度要求日益提高,微納米尺度精密儀器在表面科學(xué)、微納機(jī)電系統(tǒng)等領(lǐng)域的應(yīng)用日益廣泛。接觸與摩擦問題一直是材料設(shè)計(jì)與性能改進(jìn)方面的主要研究課題之一,研究材料微納米尺度下的摩擦學(xué)行為,揭示摩擦過程中材料的微觀變形機(jī)制與宏觀力學(xué)性能的內(nèi)，

本文編號：1443572