CAJ | 학술논문

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4 mm的玻璃棒;这些块体非晶表现出高饱和磁感应强度(0.81~1.04 T)、极低的矫顽力(0.6~1.6 A/m)、200~215 GPa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(3840~4043 MPa);用深度敏感纳米压痕技术研究了{[(Fe_(0.6)Co_(0.4))_(0.75)B_(0.2)Si_(0.05)]_(0.96)- Nb_(0.04)}_(96)Cr_4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0.75~3 mN/s加载速率下,发现了显著的锯齿流变;当增大到6 mN/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0.5 mol/L NaCl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~(-3) mm/y、从 3.9×10~(-6) 减小到 8.7×10~(-7)A/cm~2.
채용미합금화기술,용동모주조법제비Fe-Co-B-Si-Nb-Cr괴체비정합금.차조우XRD、TEM、DSC、DTA화VSM표정해파리합금계적파리형성능력화연자성능;차조동전위겁화、굉관압축시험화납미압흔기술측시해파리합금계적부식화역학성능.결과표명:Cr원소적가입,진관초미강저료Fe-Co-B-Si-Nb파리합금적형성능력,단각명현개선료타적연자성능、역학성능화부식성능;용동모주조법,가획득최대직경위4 mm적파리봉;저사괴체비정표현출고포화자감응강도(0.81~1.04 T)、겁저적교완력(0.6~1.6 A/m)、200~215 GPa적양씨모량、약2%적탄성응변화0.7%적소성응변,환옹유초고적단렬강도(3840~4043 MPa);용심도민감납미압흔기술연구료{[(Fe_(0.6)Co_(0.4))_(0.75)B_(0.2)Si_(0.05)]_(0.96)- Nb_(0.04)}_(96)Cr_4괴체비정합금적실온소성변형;해합금적납미압흔변형행위여가재속솔유관:재0.75~3 mN/s가재속솔하,발현료현저적거치류변;당증대도6 mN/s시,거치류변축점소실.령외,당 Cr 함량(원자분수%,하동)종x=0증가도x=4시,해괴체비정합금재0.5 mol/L NaCl용액중,부식속솔화부식전류밀도분별종7.0×10~(-1)감소도1.6×10~(-3) mm/y、종 3.9×10~(-6) 감소도 8.7×10~(-7)A/cm~2.
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 {[(Fe_(0.6)Co_(0.4))_(0.75)B_(0.2)Si_(0.05)]_(0.96)Nb_(0.04)}_(96)Cr_4 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/cm~2, respectively, with increasing Cr content from x=0 to x=4(at%).