Abstract
The influence of shot-peening parameters on surface integrity of 7055 aluminum alloy is investigated based on shot-peening experiments. Surface integrity measurements, fatigue fracture analysis and fatigue life tests are conducted to reveal the effect of surface integrity on crack initiation and fatigue life. The results show that surface roughness increases significantly, and irregular pits and bumps appear on surface after shot-peening; grain on subsurface is refined and produces a shift and distortion in the pellets hit direction; compressive stress can be detected on all machined surfaces. Shot-peening parameters have significant impact on micro-hardness. In comparison with the milled specimen, fatigue life of peened specimens is improved by about 23.8, 3.96 and 1.01 times. Fatigue source zone transfers from stress concentration location on surface to subsurface due to the lower surface roughness and lager residual compressive stress.
| Original language | English |
|---|---|
| Pages (from-to) | 243-256 |
| Number of pages | 14 |
| Journal | Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture |
| Volume | 231 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jan 2017 |
Keywords
- 7055 aluminum alloy
- fatigue life
- high-speed milling
- shot-peening
- surface integrity