降低ER70S-6合金焊丝用盘条强度实践

为了克服ER70S-6盘条强度高造成的拉拔困难,对比分析不同厂家生产的ER70S-6盘条钢的化学成分、金相组织和力学性能,指出盘条强度高的主要原因是珠光体含量高与晶粒度低。得出结论:(1)在成分不变的情况下,晶粒度与珠光体含量是影响抗拉强度的主要因素;(2)提高吐丝温度,在风冷线辊道速度不变的情况下,可降低盘条强度,但吐丝温度不能超过900℃。通过调整生产工艺,盘条的抗拉强度大于550 MPa的比例从原来的33%降到12%,工艺调整有效。

Practice of reducing wire rod strength of ER70S-6 alloy welding wire

In order to overcome ER70S-6 wire rod drawing difficulty due to high strength,the composition,microstructure and mechanical properties of ER70S-6 wire rod produced by different factories,and pointed out that the main cause of high strength is high pearlite content and lower grain size.Conclusion is:(1) grain size and pearlite content are main factors affecting tensile strength under the condition of composition constant,(2) to raise wire rod laying temperature can reduce wire rod strength under the condition of constant roller way speed of wind cooling line,but wire rod laying temperature is not able to be over 900 ℃.The percent of wire rod of strength over 550 MPa reduced from 33% to 12%.The adjusted process is effective.