(1. 南京航空航天大學(xué) 江蘇省精密與微細(xì)制造技術(shù)重點(diǎn)實(shí)驗(yàn)室,南京 210016;
2. 南京航空航天大學(xué) 機(jī)電學(xué)院,南京 210016)
摘 要: 利用分形幾何的原理模擬點(diǎn)陽極電沉積中枝晶的分形生長,分別研究陽極大小、射流速度、NiSO4濃度和溫度等試驗(yàn)條件對點(diǎn)陽極射流電沉積中金屬鎳枝晶二維電沉積生長行為特性的影響,并從分形維數(shù)的角度對其進(jìn)行分析。結(jié)果表明:點(diǎn)陽極射流電沉積中的枝晶也呈分形生長,其分形維數(shù)隨著點(diǎn)陽極尺寸的增大而增加;射流速度的提高使枝晶簇根部的生長點(diǎn)明顯增多,但在射流速度較低時(shí),枝晶簇頂部的形貌較為致密;大量氣泡的析出有利于產(chǎn)生分枝,此時(shí)氣泡對枝晶生長的形貌起主導(dǎo)作用,使射流速度變化時(shí)的分形維數(shù)出現(xiàn)波折;電解質(zhì)濃度的增大使枝晶簇的分形維數(shù)逐漸減小;且隨著試驗(yàn)溫度的提高,分形維數(shù)也隨之增加。
關(guān)鍵字: 鎳;射流電沉積;分形生長;枝晶
(1. Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;
2. School of Mechanical and Electronic Engineering, Nanjing University of Aeronautics and Astronautics,
Nanjing 210016, China)
Abstract:The fractal growth process of dendrite in jet-electrodeposition with point anode was stimulated. The influences of anode size, jetting speed, NiSO4 concentration and experiment temperature on the growth property of dendrite growth and fractal dimension were investigated. The results show that the dendrite of metal Ni obtained in jet-electrodeposition with point anode is also fractal growth. The fractal dimension of dendrite increases with increasing anode size. With increasing jetting speed, the growing points at the bottom of dendrite increase significantly and the morphology at the top becomes denser when the jetting speed is low. At the same time, the bubble is helpful to produce branches and takes role in the dendrite growth at high current. So, the fractal dimension twists when the jetting speed changes. The increase of concentration of NiSO4 makes the fractal dimension gradually decrease. With increasing experiment temperature, fractal dimension dendrite increases.
Key words: Ni; jet-electrodeposition; fractal growth; dendrite


