Fe-Co-B-Si-Nb-Cr软磁块体非晶合金的制备及性能  

Preparation and Properties of Fe-Co-B-Si-Nb-Cr Soft-Magnetic Bulk Amorphous Alloys

作　　者：张志纯[1] 龙志林[1] 彭建[1] 危洪清[1] 唐平[1] 李乡安[1] 

机构地区：[1]湘潭大学,湖南湘潭411105

出　　处：《稀有金属材料与工程》2010年第1期162-168,共7页Rare Metal Materials and Engineering

基　　金：湖南省教育厅重点项目(09A088);湖南省自然科学基金面上项目(09JJ6069);湖南省教育厅科学研究项目(08C880)

摘　　要：采用微合金化技术,用铜模铸造法制备Fe-Co-B-Si-Nb-Cr块体非晶合金。借助于XRD、TEM、DSC、DTA和VSM表征该玻璃合金系的玻璃形成能力和软磁性能;借助动电位极化、宏观压缩试验和纳米压痕技术测试该玻璃合金系的腐蚀和力学性能。结果表明:Cr元素的加入,尽管稍微降低了Fe-Co-B-Si-Nb玻璃合金的形成能力,但却明显改善了它的软磁性能、力学性能和腐蚀性能;用铜模铸造法,可获得最大直径为4mm的玻璃棒;这些块体非晶表现出高饱和磁感应强度(0.81～1.04T)、极低的矫顽力(0.6～1.6A/m)、200～215GPa的杨氏模量、约2%的弹性应变和0.7%的塑性应变,还拥有超高的断裂强度(3840～4043MPa);用深度敏感纳米压痕技术研究了{[(Fe0.6Co0.4)0.75B0.2Si0.05]0.96-Nb0.04}96Cr4块体非晶合金的室温塑性变形;该合金的纳米压痕变形行为与加载速率有关:在0.75～3mN/s加载速率下,发现了显著的锯齿流变;当增大到6mN/s时,锯齿流变逐渐消失。另外,当Cr含量(原子分数%,下同)从x=0增加到x=4时,该块体非晶合金在0.5mol/LNaCl溶液中,腐蚀速率和腐蚀电流密度分别从7.0×10-1减小到1.6×10-3mm/y、从3.9×10-6减小到8.7×10-7A/cm2。Fe-Co-B-Si-Nb-Cr bulk amorphous alloys with critical diameters up to 4 mm were prepared by copper mold casting method using micro-alloying technology. The glass-forming ability （GFA） and soft magnetic properties of the obtained bulk amorphous alloys were characterized by means of XRD, TEM, DSC, DTA and VSM. Corrosion and mechanical properties of bulk amorphous alloys were measured using potentiodynamic polarization, macro compressive experiment and nanoindentation testing techniques. The results show that the addition of Cr element slightly decreases GFA of Fe-Co-B-Si-Nb alloys, but is very effective in increasing corrosion resistance and improving mechanical properties and soft magnetic properties for the glassy alloys. The copper-mold-cast alloys exhibit high GFA with diameters up to 4 mm. These Fe-based bulk amorphous alloys exhibit high saturation magnetization of 0.81-1.04 T, extremely low coercive force of 0.6-1.6 A/m, Yong＇s modulus of 200-215 GPa, elastic strain of about 2% and plastic strain of 0.7%, and they also possess ultrahigh fracture strength of 3840-4043 MPa. The plastic deformation of the {[（Fe06C004）075Bo2Si005]096一Nb0.04}98Cr4 bulk amorphous alloy at room temperature was studied by depth-sensing nanoindentation technique. It is shown that the deformation behavior of the bulk amorphous alloys depends on the applied loading rate during nanoindentation. Distinct serrated flow was observed in the loading rate range from 0.75 to 3 mN/s. However, it disappeared at a loading rate of 6 mN/s. Furthermore, corrosion measurements show that corrosion rate and corrosion current density of the bulk amorphous alloys in 0.5 mol/L NaCl solution decrease from 7.0×10^-1 to 1.6 ×10^-3 mm/y and from 3.9 ×10^-6 to 8.7×10^-7 A/cm2, respectively, with increasing Cr content from x=0 to x=4（at%）.

关 键 词：铁基块体非晶合金 铜模铸造法 力学行为 软磁性能 腐蚀性能 

分 类 号：TG139.8[一般工业技术—材料科学与工程]