高强度冷拉钢丝用盘条及钢丝性能研究

High-strength wire rod and properties of cold-drawn steel wires made of it

高强度冷拉钢丝是生产建筑用预应力钢绞线和桥梁缆索用镀锌钢丝的基础材料,具有广阔的应用前景,随着技术的进步,工程建设对钢丝强度等级提出了更高的要求。对高强度冷拉钢丝用钢的化学成分、组织,生产工艺进行了研究。通过提高轧后斯太尔摩冷却速度,细化索氏体片层结构,使得盘条强度达到1 368 MPa,同时面缩率达到33%,具有良好的拉拔性能。拥有更细显微组织的高强度盘条拉拔过程中加工硬化率更高,当拉拔总压缩率达到83.8%时,5.24钢丝强度达到2 140 MPa,其强度提高的同时扭转值下降并不明显,仍达到25次,具有良好的强塑性配合。

High-strength cold-drawn steel wires have been widely used to produce PC strands and bridge cables. With the progress in technology, engineering construction demands steel wires of higher strength. The alloying composition, microstructure and production process of high-strength wire rod and cold-drawn steel wires made of it were investigated in this paper. By increasing the Stelmor cooling rate and refining the lamellar sorbite, a tensile strength of 1 368 MPa and an area contraction rate of 33 % were obtained for the wire rod, which means that it has a good drawing property. Wire rod with a thinner lamella structure showed a higher work-hardening rate, and the tensile strength reached 2 140 MPa for the φ5.24 mm wire with a drawing rate of 83.8%. The torsion value of the steel wire didn＇ t decrease obviously with the increase of strength, which suggests that it has a good combination of strength and plasticity.