冷轧低碳钢带人工时效与自然时效行为分析

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

通过对冷轧低碳钢带进行自然时效和人工时效后性能测试及组织观察,分析自然时效时间和人工时效加热温度、保温时间对其性能的影响。结果表明:冷轧低碳钢带在自然时效情况下,6个月开始出现屈服平台;强度、硬度有所提高,断后伸长率、r值、n值呈下降趋势。人工时效条件下,加热温度高于150℃,保温10min开始出现屈服平台;250℃加热,保温5min后出现较长的屈服平台,屈服强度显著提高,显微组织中铁素体基体上的游离渗碳体量显著增加。

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.