Mechanical and thermal stability of mechanically induced near-surface nanostructures

作者：Nikitin I; Altenberger I^*; Maier HJ; Scholtes B

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2005, 403(1-2): 318-327.

DOI：10.1016/j.msea.2005.05.030

• surface nanocrystallisation
• nanocrystalline materials
• transmission electron microscopy
• microstructure
• fatigue
• deep rolling

Mechanical surface treatments, such as deep rolling, shot peening, hammering, etc., can significantly improve the fatigue behaviour of metallic materials owing to near-surface nanocrystallisation, strain hardening and compressive residual stresses. In this paper, we investigate the stability of near-surface microstructures of deep rolled austenitic stainless steel AISI 304 and turbine blade alloy Ti-6Al-4V during high temperature fatigue (up to 600 degrees C) by transmission electron microscopy and X-ray diffraction. The investigated nanocrystalline regions are stable during short time annealing and unstable during long time annealing at 600 degrees C. Isothermal fatigue in the low cycle fatigue regime at high stress amplitudes does not alter the nanocrystalline region up to 600 degrees C.

• 出版日期2005-8-25