Surface strengthening of single-crystal alumina by high-temperature laser shock peening

Authors

Fei Wang, University of Nebraska-LincolnFollow
X. L. Yan, University of Nebraska–LincolnFollow
Lei Liu, University of Nebraska-LincolnFollow
Michael Nastasi, Texas A&M University, College Station
Yongfeng Lu, University of Nebraska - LincolnFollow
Bai Cui, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2021

Citation

MATER. RES. LETT. 2021, VOL. 9, NO. 3, 155–161 https://doi.org/10.1080/21663831.2020.1862933

Comments

2020 The Author(s).

Abstract

This manuscript reports a novel process of high-temperature laser shock peening (HTLSP) for surface strengthening of single-crystal ceramics such as sapphire and reveals its fundamental mechanisms. HTLSP at 1200°C can induce a high compressive residual stress on the surface of sapphire while minimize the damage of laser-driven shock waves. Transmission electron microscopy characteriza- tions revealed high dislocation densities near the surface, suggesting that plastic deformation at an ultrahigh strain rate was generated by the high shock wave pressure. The HTLSP-induced compres- sive residual stress can significantly improve the hardness and fracture toughness of sapphire, while maintain its outstanding optical transmittance.