ABSTRACT For improving the mechanical strength of cast irons, a fully pearlitic matrix is sought by alloying with tin, copper and manganese. This applies in particular to the compacted graphite irons considered here. While average macro- and micro-hardness values were similar for the four fully pearlitic alloys under study, it was found that high copper and low tin content showed some very high maximum micro-hardness values, significantly higher than the corresponding mean. Such values may be seen as hard points in the material that would certainly impair machinability. Discussion of the reasons for these extreme values opens directions for further studies.

中文翻译：

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全珠光体蠕墨铸铁显微硬度极值

摘要 为了提高铸铁的机械强度，通过与锡、铜和锰合金化来寻求完全珠光体基体。这尤其适用于这里考虑的蠕墨铸铁。虽然所研究的四种全珠光体合金的平均宏观和显微硬度值相似，但发现高铜和低锡含量显示出一些非常高的最大显微硬度值，明显高于相应的平均值。这些值可能被视为材料中的硬点，肯定会损害可加工性。讨论这些极端值的原因为进一步研究开辟了方向。