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To explore the potential beneficial effect beyond shot peening (SP)’s conventional performance, ex-situ warm shot peening (WSP) of Ti-6Al-4V coupons have been carried out. The coupons were pre-heated to 200 and 400 °C, before they were immediately transferred into a SP booth for shot-peening. While high cycle fatigue (HCF) tests did not detect a favorable improvement in fatigue life at high (0.9F0.2) and medium loadings (0.7F0.2), a significant increase in cycle-to-failure (Nf) in low loading (0.5F0.2) was observed when the ex-situ WSP temperature was raised to 200 and further to 400 °C. Center hole drilling and electron backscatter diffraction (EBSD) were employed to unveil the mechanism for such fatigue improvement.

Silica nanomaterials have found prevailing use in biomedical applications due to their biocompatibility and non-toxicity. The use of a structure-directing agent in silica sol-gel synthesis enables us to direct the formation of silica nanostructures into forms that are otherwise difficult to obtain, allowing the exertion of a fine degree of control over the morphology, dimensions and architecture of the nanostructures. Single-tailed surfactants have been used extensively as soft templates to produce mesoporous silica materials. This study investigates the use of a double-tailed surfactant, a didodecyldimethylammonium phosphate surfactant (DDAH2PO4) as a structure-directing agent in the sol-gel synthesis of silica at ambient conditions in aqueous solution. The effects of varying reaction parameters such as surfactant concentration and solution temperature on resulting silica morphology are presented. Morphological transitions from nanobeads to hexagonal plates and toroidal concave particles are observed with increasing surfactant concentrations, as well as a gradual loss in templating ability at elevated solution temperatures (up to 25 °C). This allows us to access different morphologies and dimensions of nanostructures within the same synthesis scheme templated with DDAH2PO4.