The purpose of this study was to increase the fatigue strength of single-phase CuAl8Fe3 aluminum bronze via surface cold work. CuAl8Fe3 bronze possesses a unique combination of mechanical and chemical properties: good strength, excellent electro-chemical and general corrosion resistance, high ductility and wear resistance. However, due to its low aluminum content (below 8.5%), this bronze cannot be heat treated. Thus, the fatigue strength increase was achieved via diamond burnishing (DB). The quantification of the fatigue behavior of this bronze was achieved through rotating bending fatigue tests. The assessment of the fatigue strength improvement (FSI) due to DB was made on the basis of the S–N curve obtained from fatigue tests of samples processed by fine turning. FSI due to single-pass DB fluctuates between 12 and 13%, with the maximum value achieved at the beginning of the megacycle fatigue field. The increase in the number of passes leads to a significant increase in FSI of between 16.6 and 24.4%. Since a direct correlation exists between the surface integrity (SI) and fatigue behavior, the positive effect of DB on FSI is explained by the improved SI—appropriate surface texture, increased micro-hardness, useful compressive residual stresses and grain refinement in the microstructure of the surface and sub-surface layers.

本研究的目的是通过表面冷加工提高单相 CuAl8Fe3 铝青铜的疲劳强度。CuAl8Fe3青铜具有独特的机械和化学性能组合：良好的强度、优异的电化学和一般耐腐蚀性能、高延展性和耐磨性。但是，由于铝含量低（低于 8.5%），这种青铜不能进行热处理。因此，疲劳强度的增加是通过金刚石抛光 (DB) 实现的。这种青铜的疲劳行为的量化是通过旋转弯曲疲劳试验实现的。DB引起的疲劳强度改进（FSI）的评估是在S - N的基础上进行的由精车加工样品的疲劳试验获得的曲线。由于单程 DB 导致的 FSI 在 12% 和 13% 之间波动，最大值在兆周疲劳场开始时达到。通过次数的增加导致 FSI 显着增加，介于 16.6% 和 24.4% 之间。由于表面完整性 (SI) 和疲劳行为之间存在直接相关性，因此 DB 对 FSI 的积极影响可以通过改进的 SI 来解释——适当的表面纹理、增加的显微硬度、有用的压缩残余应力和显微组织中的晶粒细化表层和次表层。