Research And Development Of High Strength And Light Weight Automotive Frame Steel

This topic is doing the research and development of 600-700MPa series high tensile light weight automotive frame steel with the help of Jigang's technology and equipment.The topic experimentized at MS-200 thermal simulation tester in Jigang technique center. C, Si, Mn as the essential component, increase right amount of microalloy element as Nb and Ti, integrated applied multi-strengthen mechanism, high strength steel has been rolled out.Via laboratory investigation, determined the technology of J610L and J700 steel, composed reasonable trial-manufacture practice.Via over-all properties detection, J610L and J700 hot rolled steel strip take on performance of high strength, excellent cold forming, favorable cold shock tenacity, fatigue resistance and solderability.What is more important, this series high strength automotive frame steel, can lighten automobile's deadweight, decrease fuel consumption, increase work efficiency, give a kind of feasible avenue for light weight automobile.This article includes:(1)J610L and J700 high strength and toughness automotive frame steel have been produced at Jigang's hot strip rolling line.Its tough-brittle transition temperature is lower than -60? with good cold bending performance.J610L steel's fatigue limit is more than 500MPa (stress ratio R=0.1) J700 steel's tensile strength is 690MPa. both are with good welding performance and high dimensional accuracy, can fit for automobile frame's technological requirements such as stamping, roll-in, knee bend, assembly etc.(2)High cleanness medium and thin slab is produced with low carbon (0.05-0.10%, high manganese (1.60-2.0%), Nb and Ti micro alloying, without any other alloying element as Mo, Cr, Ni, V, etc. reduced high cost of alloying element addition, good for smelting and recovery reuse.