Abstract: The effect of Cr element in ultra-high strength cord steel on the microstructure and properties of LX82A wire rod and drawn wire is studied by JMatPro software， metallographic microscope， scanning electron microscope and tensile properties test. The results show that：For the 82 grade cord steel，by reducing Mn content to 0.18% and increasing Cr content to 0.35%， the C curvel moves down to the right， and the strength of LX82A wire rod increases from 1 150 MPa to 1 175 MPa， and the strength of copper plated cord steel wire increases from 1 235 MPa to 1 290 MPa. The strength of finished wire is increased by 40 Mpa， and the strength of finished wire exceeds 3 650 MPa. Because the addition of Cr reduces the soxlet phase transformation temperature and refine the spacing of the lamellae ， it improves the steel wire drawing hardening ability. Through the design and application of Cr element， it improves the steel wire drawing hardening ability， improves the strength of ultra-high strength cord steel， to achieve the high strength and toughness requirements of drawing steel wire.

Key words: LX82A Cord Steel, Sorbite, Drawing Steel Hardening, Ultra-high Strength

摘要： 利用JMatPro软件、金相显微镜、扫描电镜、拉伸性能测试等方法，研究了超高强帘线钢中Cr元素对LX82A盘条及拉拔钢丝组织和性能影响。结果表明：82级帘线钢通过降低Mn含量至0.18%，提高Cr含量至0.35%，钢的C曲线往右下移动，LX82A盘条强度从1 150 MPa提高至1 175 MPa，帘线镀铜钢丝强度从1 235 MPa提高至1 290 MPa，成品钢丝强度提高40 MPa，成品钢丝强度超过3 650 MPa。由于Cr的添加降低索氏体相变温度，同时细化片层间距，提高钢丝拉拔加工硬化能力，通过Cr元素的设计应用，提高钢丝拉拔硬化能力，提高了超高强帘线钢的强度，实现拉拔钢丝高强韧性要求。

关键词: LX82A帘线钢, 索氏体, 拉拔硬化, 超高强度