去应力退火对0.1mm4J42精密合金冷轧带材性能的影响

Effect of Stress Relief Annealing on Properties of Cold Rolled Strip for 0.1 mm 4J42 Strip

采用三轧三退一次拉矫的生产工艺流程,进行引线框架用0.1 mm 4J42精密合金带材的生产。通过正交实验设定去应力退火工艺实验方案,对实验结果进行了对比分析,确定出对带材性能和板形影响最明显的因素是退火温度、其次是退火速度,最后是退火张力。并进行了相关系数计算,结果表明:去应力退火温度的变化对带材的硬度、抗拉强度、延长率影响较大,且相关度较高;而去应力退火的速度变化对带材的屈服强度影响较大,呈正相关,且相关度较高;分析了各工艺参数对带材性能的影响,并通过对板形进行对比分析,确定了最佳的去应力退火工艺:退火温度为400℃,退火速度2 m/min,张力8 kg/mm^(2),采用该生产工艺生产出来的冷轧带材板形平整。

This work focuses on the preparation process of the cold rolled strip for 0.1 mm 4J42 Strip for lead frame material.The whole process includes triple cold rolling,triple annealing and single straightening.Through the orthogonal experiment,the experimental scheme of stress relief annealing process is set.It was found that the annealing temperature,the annealing speed and the annealing tension were the most important factors affecting the strip properties and shape.The experimental results are compared and analyzed.The influence of various process parameters on the properties of the strip is analyzed,and the best stress relief annealing process is determined by analyzing the shape of the strip.The results show that the change of annealing temperature has a great influence on the hardness,tensile strength and elongation of the strip,and the correlation is high.However,the change of stress relief annealing speed has a great influence on the yield strength,showing a positive correlation,and the correlation is high.The optimum stress-free annealing process is determined as follows:annealing temperature is 400℃;annealing speed is 2 m/min;tension is 8 kg/mm^(2).The cold-rolled strip produced by this process is flat.The shape of the rolled strip is smooth and the mechanical properties is good.