【摘要】 采用工业用原材料在铜模铸造条件下制备了Fe48Cr15Mo14C15B6Y2和Fe46-xNi2Cr15Mo14C15B6Y2Nbx(x=1,2,3)块体非晶合金,研究了y(Ni)=2%和y(Nb)=1%~3%元素对合金非晶形成能力与力学性能等方面的作用.采用x射线(XRD)仪、差分扫描量热计(DSC)、万能材料力学实验机和扫描电镜(SEM)对铸态样品的相组成、非晶合金的热稳定性、合金的断裂强度及其断口形貌进行了研究.实验结果表明:Fe45Ni2Cr15Mo14C15B6Y2Nb1可以形成直径超过5 mm的大块非晶合金,与Fe48Cr15Mo14C15B6Y2相比,非晶形成能力获得了较大的提高.并且Fe48Cr15Mo14C15B6Y2和Fe46-xNi2Cr15Mo14C15B6Y2Nbx(x=1,2)非晶合金的约化玻璃转化温度和过冷液相区的大小与合金的非晶形成能力有良好的对应关系,但合金的力学性能有所降低.合金断口均表现为典型的脆性断裂特征.更多还原

【Abstract】 Bulk metallic glasses with compositions of Fe48Cr15Mo14C15B6Y2 and Fe46-xNi2Cr15Mo14C15B6Y2Nbx(x=1,2,3) were fabricated by copper mold casting method using raw industrial materials.The effect of substituting 2at%Ni and 1～3at%Nb for Fe on glass forming ability and mechanical properties was investigated for Fe48Cr15Mo14C15B6Y2 alloy.The XRD,DSC,universal mechanical tester and SEM were employed to check the phase constituent,thermal stability,mechanical properties and fracture surfaces of as-cast samples.The results indicate that the bulk metallic glass with a diameter over 5 mm can be formed for Fe45Ni2Cr15Mo14C15B6Y2Nb1 alloy.The glass-forming ability is greatly improved compared with the original Fe48Cr15Mo14C15B6Y2 alloy.The reduced glass transition temperature and supercooled liquid regions of Fe48Cr15Mo14C15B6Y2 and Fe46-xNi2Cr15Mo14C15B6Y2Nbx(x=1,2) amorphous alloys are well correspondent to the glass-forming ability of those alloys,while the compressive strength decreases.The fracture surfaces of all bulk metallic glasses exhibit typical brittle fracture feature.更多还原