Analysis on Artificial Aging and Natural Aging Behavior of Cold Rolled Low Carbon Steel Strip

Through mechanical property testing and microstructure observation for cold rolled low carbon steel strip with natural aging and artificial aging,the effect of natural aging time,artificial aging heating temperature and holding time on the properties was analyzed.The results showed that under the condition of natural aging,the yield platform started to appear for six months;the strength and hardness increased,the break elongation,r and n value were on the decline.Under the condition of artificial aging,the yield platform started to appear as the heating temperature higher than 150 ℃,the heat preservation for 10 min.A longer yield platform appeared under 250 ℃ for 5 min,the yield strength improved significantly,and the free carburizing volume on ferrite matrix increased significantly.