正火温度对A573Gr.70容器钢带状组织和力学性能影响

Effect of Normalizing Temperature on Banded Structure and Mechanical Properties of A573Gr.70 Vessel Steel

研究了系列正火热处理工艺对A573Gr.70钢带状组织和力学性能的影响,分析了带状组织形成原因,提出了A573Gr.70钢的最佳热处理工艺制度。试验结果表明,随着正火温度的升高,带状组织等级逐渐降低,力学性能得到改善。当正火温度达到940°C时,带状组织基本消除,钢板的强韧性匹配达到最佳状态。

The effect of the series of normalizing processes on the banded structures and mechanical properties of A573Gr.70 steel plate was studied. Then the causes leading to the formation of banded structures was analyzed and thus the optimal heat treatment scheme for A573Gr.70 steel was proposed. The test results showed that the banded structure level was lowered with the increasing of normalizing temperature while the mechanical properties were improved. As the normalizing temperature came up to 940℃, the banded structure was eliminated basically. As a result, the matching for strength and toughness of the A573Gr.70 steel was in optimum condition.