Effect of V and N on Microstructures and Properties of Cold Drawn High Carbon Steel

In order to enhance the strength of cold drawn high carbon steel and improve its comprehensive properties ,the law of change in microstructures and properties of high carbon steel with various contents of V and N were investigated .The size of pearlite colony，interlamellar spacing of pearlite and mechanical properties with various contents of V and N were measured; the change of magnetic properties of wires with different cold drawing strains were measured by VSM. It is shown that V can decrease the size of pearlite colony and interlamellar spacing of pearlite when V content is less than 0.06 wt %; N can decrease the size of pearlite colony and increase slightly the interlamellar spacing of pearlite. The tensile strength is enhanced with increasing V or N content, but V decrease plasticity of wire and N has little effect on it. The cementite in wire is dissolved with increasing cold drawing strain. The volume fraction of cementite is decreased to 4.4%，dissolution of 7.8%，as the true strain is increased up to 3.19.