超细Ni80Cr20合金丝的冷拉拔制备及表征

开展特定直径超细Ni80Cr20合金丝的冷拉拔制备研究,并通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)和金属丝强力仪等对超细合金丝进行了表征。研究结果表明:烧头过程最佳电解液浓度为0.05mol/L,时间为3s;制备的镍铬合金丝直径为24.54μm,表面光滑,尺寸精准;拉拔后晶粒尺寸减小,退火后晶粒尺寸长大;拉拔态镍铬丝由于加工硬化,其伸长率由16%降低至1.88%;退火可改善镍铬丝性能,其断裂强度降低,伸长率增大,合金塑性增强,氮气退火丝的断裂强度大于真空退火丝的断裂强度,伸长率则相反。

Preparation and characterization of ultra-thin Ni80Cr20 alloy wire by cold drawing

The preparation process of ultrafine ultra-thin Ni80Cr20 alloy wire was studied by cold drawing. The property of NiCr alloy wire was characterized by SEM, XRD and tensile tester. The results show that the optimal electrolyte concentration and time were 0.05 mol/L and 3 s in the process of electrolytic corrosion, respectively. NiCr alloy wire with a smooth surface, precise dimensions and the diameter range of 24.54 μm was obtained. After drawing, the grain size decreased, and the grain size grew up after annealing. Due to work harding appearing in the drawing process, the elongation decreased from 16% to 1.88%. The fracture strength decreases and the elongation and plasticity increases after annealing. The fracture strength of wire annealed in N₂ is greater than in vacuum. On the contrary, the elongation of wire annealed in N₂ is less than in vacuum.