辊轮转速对Ni-Zr-Ti基非晶纤维形貌及拉伸强度的影响  

Morphology and Tensile Strength of Ni-Zr-Ti Based Glassy Fibers with Different Wheel Speeds

作　　者：邹成路[1] 耿桂宏[1] 刘利盟[1] 张蔚冉[1] 薛鹏皓 

机构地区：[1]北方民族大学材料科学与工程学院,宁夏银川750021

出　　处：《稀有金属》2017年第6期714-719,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51561001);宁夏高等学校科研项目(NGY20140132)资助

摘　　要：利用高真空单辊熔体抽拉技术制备出了形貌均匀、性能优异的Ni-Zr-Ti基非晶纤维。讨论了制备过程中辊轮转速变化对所制备合金纤维的表面形貌、显微结构及拉伸强度的影响。结果表明:Ni-Zr-Ti基合金纤维的宏观形貌及微观结构对辊轮转速均存在较强的工艺依赖性。随着辊轮转速增加,纤维的厚度变化较小而宽度明显降低,纤维截面圆整度及表面形貌均匀性得到相应改善。当辊轮转速达到20 m·s^(-1)时,纤维中出现Ni_2Si相析出,析出的第二相有效抑制剪切带扩展,导致纤维在拉伸断裂前出现轻微屈服应变并在断口处留下近似韧窝状的断裂花样。当辊轮转速高于30 m·s^(-1),所制备的各组纤维均处于完全非晶态。当转速达到80 m·s^(-1)时,配合5.86 mm·min^(-1)的进给速度可使纤维的截面圆整度及平均拉伸强度(1490 MPa)达到最优值。Ni-Zr-Ti based glassy fibers with uniform morphology and excellent properties were fabricated by melt extraction in high vacuum. Effects of the copper roller rotation speeds on the fiber morphology, micro structure and the tensile strength were investigated. The results showed a strong dependence of the fiber macroscopic surface and micro structure on the roller rotation speeds. With the roll- er speed increasing, the thickness of the fiber varied a little and the width of the fiber decreased significantly. At the same time, the roundness of the fiber cross-section and the uniformity of the surface morphology were correspondingly improved. A Ni2Si phase was precipitated at 20 m s-1 which inhibited expansion of the shear bands and thus gave a slight yielding strain and dimple patterns on the fracture surfaces of the fibers. When the roller speed was increased to 30 m s-l and above, the fiber was completely glassy. The fiber that was fabricated at 80 m s-1 with a feeding rate of 5.86 mm min-1 reached a high tensile strength up to 1490 MPa.

关 键 词：Ni-Zr-Ti合金 玻璃态纤维 熔体抽拉 拉伸强度 相分离 

分 类 号：TG146.1[一般工业技术—材料科学与工程]