Page 26 - 理化检验-物理分册2024年第八期

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试验与研究 DOI:10.11973/lhjy-wl230234

汽车车轮用高扩孔率热轧复相钢带的研制

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左 鹏 ，管传华 ，邬晓燕 ，许鹤君 2
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（1.宁波钢铁有限公司 技术中心，宁波 315807；2.上海材料研究所有限公司 检测中心，上海 200437）
摘 要：设计了一种微合金化的汽车车轮用高扩孔率热轧复相钢，并对其进行了工业试制。采用
金相检验、力学性能测试等方法研究了高扩孔率热轧复相钢的显微组织及力学性能。结果表明：试
制产品的显微组织主要由贝氏体、铁素体构成，还分布有少量的马氏体、残余奥氏体以及弥散析出
的第二相粒子，产品的屈服强度、抗拉强度、断后伸长率分别超过了520，610 MPa和24%，屈强比为
0.85~0.87，扩孔率达到83%以上，沿板宽方向的扩孔率在10%以内波动；增加Si元素含量能明显
改善扩孔性能，同时会影响产品的表面质量，将Si元素的质量分数控制在0.20%左右较为合适；试
制产品具有优异的局部成形性、良好的抗疲劳性和焊接性能，在疲劳试验承载力为1 700 N · m的条
件下，车轮弯曲疲劳寿命达到60万次以上。
关键词： 热轧复相钢带；高扩孔率；汽车车轮；显微组织；力学性能；扩孔率；疲劳寿命
中图分类号：TG115.2；TB31 文献标志码：A 文章编号：1001-4012(2024)08-0010-06

Development of high hole-expanding ratio hot-rolled complex phase
steel for automotive wheels

ZUO Peng , GUAN Chuanhua , WU Xiaoyan , XU Hejun 2
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(1.Technology Center, Ningbo Iron & Steel Co., Ltd., Ningbo 315807, China;
2.Testing Center, Shanghai Research Institute of Materials Co., Ltd., Shanghai 200437, China)
Abstract: A micro-alloyed hot-rolled complex phase steel with high porosity for automobile wheels was designed
and industrially trial-produced. The microstructure and mechanical properties of hot rolled multiphase steel with high
hole expansion rate were studied by means of metallographic examination and mechanical properties test. The results
show that the microstructure of the trial product was mainly composed of bainite and ferrite, and a small amount of
martensite, retained austenite and dispersed second phase particles were also distributed. The yield strength, tensile
strength and elongation of the product exceed 520, 610 MPa and 24%, respectively. The yield ratio was 0.85~0.87,
the hole expansion rate was more than 83%, and the hole expansion rate along the width of the plate fluctuated within
10%. Increasing the content of Si element could significantly improve the hole expansion performance and affect the
surface quality of the product. It was more appropriate to control the mass fraction of Si element at about 0.20%. The trial
product had excellent local formability, good fatigue resistance and welding performance. Under the condition of fatigue
test bearing capacity of 1 700 N·m, the bending fatigue life of the wheel reached more than 600 000 times.
Keywords: hot-rolled complex phase steel strip; high hole expansion rate; car wheel; microstructure; mechanical
property; reaming rate; fatigue life

汽车轻量化技术正处于快速发展阶段，钢制车 成的车轮较原普通低合金、高强度车轮减重10%以
[1]
轮是汽车的重要零部件，也向着高强度、薄规格方向 上 。浙江市场上汽车车轮用钢年需求量近10万吨，
发展，采用强度为600 MPa级的高强度钢铁材料制 市场容量较大，但普遍强度在500 MPa以下。传统
高强度汽车车轮用钢已经开始用于制造汽车轮辐，
但汽车轮辋的制造仍存在技术瓶颈，主要体现在对
收稿日期：2023-08-14
[2]
焊部位扩口开裂 、轮辋滚压成型开裂、轮辐和轮辋
作者简介：左 鹏（1989—），男，学士，工程师，主要从事金属材
料研发工作，zuopeng@ningbosteel.com 组合焊接热影响部位疲劳强度不足等。制造轮辋对
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