Analysis and Control on the Edge Cracking of Hot-Rolled Strips

The cause of edge cracking defect of hot-rolled strips was investigated and analyzed by metallographic microscope,SEM and process investigation.The results showed that bad deoxidization during smelting and the unstable casting operation are the main causes for continuous edge cracking of strips;The overheating and overburning of slab during ready rolling stage are the main causes for non-continuous edge cracking of strips.According to study results,the process was optimized and better results were obtained,the rate of edge cracking defects of slab decreased from 80~85 heats/month to 4~5 heats /month,the continuous edge cracking of hot-rolled strips was almost eliminated and the rate of the noncontinuous edge cracking of hot-rolled strips decreased from 17.6% to 1.2%.