A comprehensive investigation of phase evolution of Al-Si coating during the prolonged aging at 650 °C

•The Al-Si coating deposited on Super304H was aged at 650 ℃ for up to 10,000 h.•A complete phase evolution diagram of the coating is established.•Interdiffusion is hindered by a continuous barrier layer composed of Cr3Si.•A prediction of phase evolution is given based on the change of elemental content.