冷轧过程中过共析钢的组织演变和形变强化

Microstructure Evolution and Mechanical Hardening of Hyper-Eutectoid Steel During Cold Rolling

用SEM、TEM研究了不同冷轧变形量（变形量0～8l_6％）的过共析钢的组织演变规律。结果表明，由于珠光体片层取向的多样性，造成了不同珠光体团变形的不均匀性，随着变形量的增大，组织经历了一个由均匀一不均匀一均匀的过程；通过XRD分析，确定在冷轧变形过程中未发现渗碳体分解并溶人铁素体的现象；通过力学性能测定，发现屈服强度Rel与真应变ε基本符合Hollomon关系，可用方程Rel=1465ε^0.18预测不同变形量下试验钢的屈服强度。

Microstructure evolution of hypereutectoid steel duning cold rolling with different reduction rate （from 0 to 81.6%）was studied by SEM and TEM. The results showed that due to orientation multiplicity of pearlitic lamellas the non-uniform deformation of different pearlitic blocks are observed and with the increase of reduction rate the microstructure undergoes a course of ＂uniformity→non-uniformity→uniformity＂; results of XRD analysis indicated that cementite doesn＇t decompose and dissolve into ferrite; mechanical test results suggested that relationship be- tween ReL （yield strength）and e （true strain）is in accord with Hollomon relationship and yield strength of the steel under different reduction rate can be predicted by the equation Rel=1465ε^0.18.