(1. 中南大學(xué) 粉末冶金國家重點實驗室,長沙 410083;
2. 昆明理工大學(xué) 材料科學(xué)與工程學(xué)院,昆明 650093)
摘 要: 采用溶膠-凝膠法,通過控制正硅酸乙酯(TEOS)和3-氨丙基三乙氧基硅烷(APTES)偶聯(lián)劑的加入量,在Fe85Si9.6Al5.4粉末表面包覆SiO2絕緣層。采用X射線衍射(XRD)、傅氏變換紅外光譜(FTIR)、X射線光電子能譜(XPS)、掃描電鏡(SEM)和磁力顯微鏡(MFM)對粉末的微觀結(jié)構(gòu)及成分進行表征,采用振動樣品磁強計(VSM)測試粉末的磁性能。結(jié)果表明:利用硅烷偶聯(lián)劑對Fe85Si9.6Al5.4粉末表面改性后再加入TEOS,能在Fe85Si9.6Al5.4粉末表面包覆一層約1~2 μm厚的絮狀非晶SiO2;隨著TEOS和APTES添加量的增多,SiO2包覆層的厚度也隨之增加,飽和磁化強度Ms在0.86~0.90 T之間變化,Hci基本不變;當添加6 mL TEOS、1 mL APTES時,得到的包覆粉末包覆效果及性能最佳,飽和磁化強度Ms達到0.90 T,矯頑力Hci為1 114 A/m。
關(guān)鍵字: Fe-Si-Al粉末;軟磁復(fù)合粉末;溶膠-凝膠法;SiO2絕緣包覆層
(1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. School of Materials Science and Engineering, Kunming University of Science and Technology,
)
Abstract:Silica insulation coatings were prepared on the surface of Fe85Si9.6Al5.4 powder by sol-gel method through controlling the additions of tetraethyl orthosilicate (TEOS) precursor and (3-Aminopropyl) triethe-oxysilane (APTES) coupling agent. The microstructures, composition and magnetic properties of the material were characterized by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), magnetic force microscopy (MFM) and vibrating sample magnetometry (VSM). The results show that the compact amorphous silica layers with a thickness of 1-2 μm are coated on the surface of the Fe85Si9.6Al5.4 powder after surface modification by APTES and then followed by addition of TEOS. The thickness of silica layer increases with increasing the addition of TEOS and APTES, and the saturation magnetization (Ms) varies between 0.86 T and 0.90 T, with coercivity basically unchanged. The optimal coating effect and properties can be obtained by adding 6 mL TEOS and 1 mL APTES, with saturation magnetization and coercivity reaching 0.90 T and 1 114 A/m, respectively.
Key words: Fe-Si-Al powder; soft magnetic composite powder; sol-gel method; SiO2 insulation coatings


