Peening atomic

Ion implantation of ceramic surfaces can reduce the fracturing of brittle surfaces under load by the introduction of a compressive stress in the surface region both by atomic peening and by surface-region amorphization that is accompanied by a volume expansion. Amorphitizing the surface of ceramics improves their fracture resistance and provides better wear resistance, even though the surface hardness may be decreased. 

Bombardment during film growth densifys the film, causes recoil displacement of near-surface atoms (atomic peening), causes sputtering and redeposition, and adds thermal energy. 

High residual compressive growth stresses can be built into the film due to atomic peening. ... 

Particle bombardment of the growing surface causes atomic peening , where surface atoms are struck and recoil into voids and interstitial sites in the lattice of the surface region. This causes densification of the material and introduces compressive stresses into the film. The densification... 

Atomic peening (film formation) The continuous or periodic bombardment of a depositing film with high energy atoms or ions to density the depositing film material. Atomic peening tends to introduce compressive stress into a surface or growing film. 

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