φ5.35mm-2100MPa桥梁用锌铝钢丝的工艺与组织性能

 为了制备更高强度级别的桥梁缆索用热镀锌铝钢丝，通过对高碳钢盘条的成分设计、低损伤拉拔技术以及热浸镀锌铝等工艺过程的优化，成功试制出?5.35 mm-2 100 MPa级桥梁缆索用热镀锌铝钢丝。设计的SWRS92Si盘条主要成分为（质量分数）：C 0.90%～0.95%，Si 0.8%～1.1%，Cr 0.20%～0.30%。试制结果表明，?13 mm-SWRS92Si盘条经铅浴处理后，珠光体层片平均尺寸从120下降至90 nm，盘条强度上升约260 MPa。经冷拉拔与热镀锌铝后，层片宽度约40 nm的珠光体层片未明显球化，可制备出2 100 MPa级直径5.35 mm的桥梁缆索用热镀锌铝钢丝。钢丝的平均抗拉强度为2 128 MPa，平均断后伸长率为5.4%，扭转圈数平均值为22圈，断口均为平断口，镀层较均匀致密；其他性能指标均优于交通部标准JT/T 1104—2016《桥梁用热镀锌铝合金钢丝》中的要求。

Manufacturing technology，microstructural and mechanical properties of ?5.35 mm-2 100 MPa grade hot galvalume steel wire for bridge cable

In order to prepare the higher strength grade of bridge cables，the bridge cables use galvanized aluminum wire 2 100 MPa grade hot-dip galvalume steel wires with a diameter of 5.35 mm was developed through the composition design of high carbon steel rod，low damage drawing technology and optimization of hot-dip process. The main composition of designed SWRS92Si steel rod was 0.90%-0.95% C，0.8%-1.1% Si and 0.20%-0.30% Cr. Experimental results showed that the ?5.35 mm-2 100 MPa wire could be manufactured by using ?13 mm-SWRS92Si rod after lead patent. The average interlamellar spacing of pearlite in steel rod was decreased from 120 nm to 90 nm after lead patenting，and rod strength increased by about 260 MPa. After cold drawing，the interlamellar spacing of pearlite in the steel wire was decreased to about 40 nm. Spheroidizing cementite could not observed in the pearlitic wire after hot galvalume. The tensile strength and average elongation of wire were about 2 128 MPa and 5.4%，respectively. The torsion cycles of the wire were about 22，and the torsion fracture was cleavage fracture. Other properties of the wires were met the requirements of Chinese Ministry of transportation standards JT/T 1104—2016.