The invention discloses a preparation method for a MoSi2
coating on surfaces of
metal tantalum and an
alloy. The preparation method comprises the steps that S10, a
tantalum substrate is provided, and the
tantalum substrate is polished and cleaned to remove oxides and impurities on the surface of the tantalum substrate; S11, an osmotic agent
raw material, which comprises an activator, a dispersant,
molybdenum powder and
silicon powder, is provided; S12, the
molybdenum powder, the activator and the dispersant are mixed according to a
mass part ratio of (40-50):(5-10):(40-55) to form a first mixture; S13, the tantalum substrate is buried in the first mixture, is subjected to heat preservation for 4-10 h at 1300-1500 DEG C in a protection
atmosphere, and is taken out and cleaned; S14, the
silicon powder, the activator and the dispersant are mixed according to a
mass part ratio of (20-40):(5-18):(55-75) to form a second mixture; and S15, the product obtained in the step S13 is buried into the second mixture, is subjected to heat preservation for 8-20 h at 1100-1400 DEG C in the protection
atmosphere, and is taken out and cleaned, so that a sample with the MoSi2
coating is obtained.