辛丽
,
周龙江
,
李美栓
,
李铁藩
中国腐蚀与防护学报
利用热重分析(TGA)、扫描电镜、能谱分析、电子探针及X射线衍射等技术研究了离子注入1×10~17Y~+/cm~2对Ni30Cr定向凝固合金1000℃恒温氧化行为的影响。合金的横向和纵向虽具有不同的显微结构,但氧化行为相似。注入Y~+降低了合金的氧化速率约1～2倍,细化了氧化膜晶粒,抑制了晶界优先氧化及内氧化现象的发生,减少了界面空洞,增强了膜的粘附性。产生上述结果的原因在于注入Y~+改变了合金的氧化机制,未注Y~+合金的氧化膜主要靠铬向外扩散生长,注Y~+合金则主要靠氧向内扩散生长。
关键词:
氧化
,
Ion implantation
,
Yttrium
,
Ni-Cr alloy
,
Directional solidification
G.X. Cai
材料科学技术（英）
Ion implantation is a powerful method for fabricating nanoparticles in dielectric. For the actual application of nanoparticle composites, a careful control of nanoparticles has to be achieved. In this letter, the size, distribution and morphology of Ag nanoparticles are controlled by controlling the ion current density, ion implantation sequence and ion irradiation dose. Single layer Ag nanoparticles are formed by Ag+ ion implantation at current density of 2.5 μA/cm2. By Ag and Cu ions sequential implantation, the size of single layer Ag nanoparticles increases. While, by Cu and Ag ions sequential implantation, uniform Ag nanoparticles with wide distribution are formed. The morphology of Ag nanoparticles changes to hollow and sandwiched nanoparticles by Cu+ ion irradiation to doses of 3×1016 and 5×1016 ions/cm2. The optical absorption properties of Ag nanoparticles are also tailored by these ways.
关键词:
Nanoparticles
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,
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