新型超高强度钢零件热冲压技术

摘要

为克服现今热冲压的难题,开发了一种高强度钢零件的新型热冲压技术.利用快速电阻加热,该热冲压技术所需的设备比电炉加热的设备更简单.与传统液压加工相比,该工艺采用机械伺服高速冲压可以提高成形性.通过具有局部旁路电阻加热的剪切模具,制备了具有不同强度分布的零件.局部电阻加热使得剪切区的流变应力减小,从而使模具淬火钢零件和超高强钢板的剪切更容易.通过对杯壁进行电阻加热,利用热齿键成型技术制备了超高强度钢齿轮盖.同时,还通过热冲压成型制备了汽车用中空导流槽.一次热压成形工艺包括电阻加热、成形、剪切和模具冷却等流程,该工艺适用于相对较小的高强度钢零件.%Smart hot stamping processes of ultra-high strength steel pans have been developed to overcome difficulties in the present hot stamping process.Using rapid resistance heating,the stamping equipment became considerably simpler than that using furnace heating.The formability was improved by high speed hot stamping using a mechanical servo press in comparison with the conventional process using a hydraulic press.Parts having a different distribution of strength were produced by tailored die quenching using local bypass resistance heating.Die-quenched steel parts and ultra-high strength steel sheets were sheared by reducing the flow stress in the shearing zone using local resistance heating.An ultra-high strength steel gear drum was produced by hot spline forming using resistance heating of side wall of a cup.V-shaped hot forming using sealed air was developed to produce ultra-high strength hollow axle beams used for suspensions of automobiles.A one shot hot stamping process consisting of resistance heating,forming,shearing and die quenching was applicable to comparatively small high strength steel parts.