问题 问答题 简答题

钢板冷却过程中容易产生的缺陷有哪些?其产生原因?

答案

参考答案:

产生的缺陷有:冷却裂纹和残余应力、组织性能不好、瓢曲和划伤等。

1)冷却裂纹和残余应力是由于钢板在冷却时,由于不均匀冷却所产生的热应力造成的。

2)钢板在冷却时,如果冷却过慢则使晶粒粗大,冷却速度过快又会产生魏氏组织、马氏体组织等,降低钢板的综合力学性能。

3)瓢曲是由于钢板冷却时,上下表面冷却不均以及各部位冷却不均所造成的。

4)划伤是在钢板运行时,由于温度较高、冷床表面不平所产生的缺陷。

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       I work in the school library. There are many kinds of   1    in it. For example, books about English,
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配伍题 B1型题