Abstract: By means of tensile test,hardness testing and scanning electron microscope observation,the effects of sampling direction,parallel length,baking temperature and baking time on the yield strength,microstructure and hardness of MR T-3 BA and MR T-4 CA tinplates were analyzed.The results showed that the sampling direction had a great influence on the yield strength of the two tinplates.The yield strength of the MR T-3 BA tinplate in the 0°direction was higher than that in the 90°and 45°directions,and the yield strength of the MR T-4 CA tinplate in the 90°direction was higher than that in the 0°and 45°directions.Under the condition of different parallel lengths,the yield strength of the two tinplates had no significant difference.With the increase of baking temperature,both the yield strength and hardness of MR T-3 BA tinplate showed an upward trend,and the grains became finer,while the yield strength of MR T-4 CA tinplate decreased slightly,and its hardness and microstructure did not change significantly.The baking time had little effect on the yield strength,hardness and microstructure of the two tinplates.