Alpha alumina synthesis by laser treatment of bi-phasic nanowires

► Laser treatment of bi-phasic Al/Al2O3 nanowires lead to dense and fully crystalline alumina (crack free). ► We present visible laser assisted ceramic synthesis instead of using CO2 laser. ► We present a dynamic surface which reflects the laser light after the phase transformation. ► Laser treated surface exhibits a hardness comparable to single crystalline alumina (sapphire).