The surface or sheath effect on core-shell nanowires plays an important role in the nanomechanical test. In the past few years, SiC nanowires have been synthesized using various methods with an uneven and uncontrollable amorphous silicon dioxide sheath. The bending Young’s modulus of the SiC nanowires has scarcely been measured, and the effect of the oxide sheath has not been taken into account. In this paper, SiO₂-coated SiC (SiO₂@SiC) nanowires were synthesized using the chemical vapor deposition method, followed by thermal reduction. Scanning electron microscopy and transmission electron microscopy show that the SiO₂@SiC nanowires in this paper have diameters ranging from 130 ~ 150 nm, with the average thickness of SiO₂ layer approximately 14 nm. After different processing times with 1 mol/L NaOH, approximately 5 nm, 9 nm, 14 nm silicon dioxide layers were obtained. The results of the three-point-bending test show that the modulus of SiO₂@SiC nanowires is found to clearly decrease with the increase in oxide thickness and the influence of the oxide sheath should not be ignored when the layer thickness is above 5 nm. Young’s modulus of the SiO₂@SiC nanowires calculated in this study by the core-shell structure model is in good agreement with the theoretical value.

Micro targeted therapy for cancer has become a hot topic in recent years because of its advantages of little damage to the human body and early treatment of cancer.