大应变变形珠光体钢丝微观组织结构的研究

  采用扫描电镜（SEM）观察了以不同应变量拉拔变形后SWRH72A钢丝的显微组织变化，并测量了钢丝力学性能、磁学性能随应变量增大的变化趋势。试验结果表明，随着拉拔变形应变量的增大，珠光体片层间距逐渐减小，钢丝强度随之升高。由于变形应变量的增大，微缺陷密度升高，钢丝矫顽力Hc和剩余磁化强度Mr都随之变大。而应变量较小时，钢丝比饱和磁化强度基本不变，为227.87 emu/g。当应变量增大到2.60时，样品的比饱和磁化强度升高到233.55 emu/g，计算得知钢丝中渗碳体的质量分数由未变形状态的10.8%降至8.6%。

Study on Microstructure of Heavily Drawn Pearlite Steel Wire

The microstructure of havily drawn SWRH72A wire was studied with SEM. The change of mechanical properties and magnetic properties of the wire with the increase of drawing strain were investigated. The results show that the interlamellar spacing of pearlite is decreased progressively during the cold drawing. Tensile strength,coercive force and residual magnetization of the wire are increased with increasing drawing strain.When the strain was small, the saturation magnetization of the wire was almost unchanged,227.87 emu/g.But increased to 233.55 emu/g with the strain increasing to 2.60.As calculated,that part of cementite was decomposed in heavily drawn SWRH72A steel.