Effect of Cu alloy element on the performance of powder metallurgy surface rolling densification
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摘要: 表面滚压致密化工艺不仅能降低齿轮齿面的噪音,还能提高齿轮齿面的抗滚动接触疲劳性能,在粉末冶金齿轮生产领域得到广泛应用。滚压粉末冶金坯料的原始成分对滚压致密化效果有很大的影响,本文研究了合金元素Cu的质量分数对滚压效果的影响,从材料的孔隙情况、组织结构、硬度、耐磨性等方面分析讨论了表面滚压致密化工艺原料的选择问题。结果表明,坯料原始成分中Cu质量分数对齿轮用粉末冶金零件的表面致密化行为和性能起到重要作用,Cu质量分数越低,材料的合金化程度越低,塑性变形抗力越低,在相同的滚压条件下,可以获得较好的表面致密化效果;Cu质量分数的增加有利于提高零件的硬度和耐磨性,当Cu质量分数为1.4%时,零件表面致密层深度为1.13 mm,耐磨性较高,具有最优的综合性能,更适合实际工况的应用。Abstract: Rolling densification process is widely used in manufacture field of powder metallurgy gears, which could reduce the noise and enhance the rolling contact fatigue performance of gears. The original composition of powder metallurgy blank parts has a significant effect on the performance of surface rolling densification. The effect of Cu content by mass on rolling densification was studied in this paper, the influences of raw materials on porosity, structure, hardness, and wearing resistance of powder metallurgy gears in the surface rolling densification process were analyzed and discussed. The results show that, Cu plays an important role on the densification behavior and the properties of powder metallurgy gear parts. Under the same rolling parameters, the parts with lower Cu content have better surface densification performance because of the lower degree of alloying. However, the increase of Cu content is conducive to improve the hardness and wearing resistance of the parts. The parts with 1.4% Cu by mass have the surface dense layer in 1.13 mm and show the high wearing resistance, which have the best overall performance and are more suitable for the actual working conditions applications.
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Key words:
- surface rolling densification /
- powder metallurgy /
- alloy element /
- copper /
- plastic deformation
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表 1 实验原料化学成分(质量分数)
Table 1. Chemical composition of raw material
% 试样编号 Astaloy85Mo C Cu 1 余量 0.8 — 2 余量 0.8 1.0 3 余量 0.8 1.4 4 余量 0.8 2.0 -
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