论文部分内容阅读
为了扩展粉末冶金的业务,改进动态力学性能和搜集这样的数据是必要的。我们长期认为部分扩散粘结合金较适合达到较高的疲劳强度,对于在某些作业条件下的零件的确是这样。然而,现在粉末冶金零件的密度水平在提高。高密度和后续加工的最佳化相结合表明,与部分扩散粘结合金相比,预合金化的材料更适于得到高得多的疲劳强度。于是,开展了一些改善疲劳强度的研究。本文介绍了通过应用喷丸法改善疲劳强度,而且通过分析应力曲线讨论了改善疲劳强度的机制。还讨论了几何形状对应力曲线的影响,其中包括对实际的变速器齿轮的FEM分析,以此来描述每一零件的最佳后续加工方法。对于一个实际的变速器齿轮使用粉末冶金零件的可能性,在这篇论文中,通过用测量嵌进实际变速器齿轮箱中的齿轮的齿根应力计算的安全系数进行了讨论。
In order to expand the business of powder metallurgy, it is necessary to improve dynamic mechanical properties and collect such data. We have long believed that some diffusion bonding alloys are better suited to achieve higher fatigue strength, indeed for parts under certain operating conditions. However, the density of powder metallurgy parts is now on the rise. The combination of high density and optimization of subsequent processing has shown that pre-alloyed materials are more suitable for obtaining much higher fatigue strength than partially diffusion bonded alloys. As a result, a number of studies have been conducted to improve fatigue strength. This article describes the improvement of fatigue strength by the application of shot peening and discusses the mechanism for improving fatigue strength by analyzing stress curves. The effect of geometry on stress curves is also discussed, including FEM analysis of actual transmission gears to describe the best way to follow each part. The possibility of using powder metallurgy parts for an actual transmission gear is discussed in this paper by using a safety factor calculated by measuring the root stress of the gear embedded in the gearbox of the actual transmission.