YSZ (Yttria Stabilized Zirconia)-based composite thermal barrier coating material and preparation method thereof

Abstract

The invention discloses a YSZ (Yttria Stabilized Zirconia)-based composite thermal barrier coating material and a preparation method thereof. The thermal barrier coating material is prepared with a method for spraying plasma onto composite powder of a calcium silicate-coated YSZ material with a core-shell structure. The internal structure of the YSZ-based composite thermal barrier coating material is dense, air holes and micro-cracks are distributed more uniformly, the hole diameters of the air holes are smaller, crystal grains of a coating are relatively uniform and small, and the average size of the crystal grains is about 0.5 mum; the temperature conductivity coefficient is remarkably lowered, and the temperature conductivity coefficients of the material at the temperatures of 900 DEG C and 1,200 DEG C are lowered by 16 percent and 10 percent respectively in comparison to those of the conventional YSZ material; the heat conductivity is remarkably lowered, and the heat conductivity of the material at the temperatures of 900 DEG C and 1,200 DEG C is lowered by 27 percent and 20 percent respectively in comparison to those of the conventional YSZ material; high-temperature anti-sintering capability is high, and a good heat insulating effect is achieved; and moreover, a preparation process is simple, and is suitable for large-scale production.

Description

technical field [0001] The invention relates to a thermal barrier coating material and a preparation method thereof, in particular to a calcium silicate-modified YSZ-based composite thermal barrier coating material and a preparation method thereof, belonging to the technical field of thermal barrier coating materials. Background technique [0002] Incorporating yttria-stabilized zirconia (YSZ) due to its low thermal conductivity (~2.3W·m -1 ·K -1 , 1000°C) and high coefficient of thermal expansion (~11×10 -6 ℃ -1 ), can produce obvious heat insulation effect, and can effectively weaken the ceramic coating and substrate (the coefficient of thermal expansion is ~14×10 -6 ℃ -10 ) thermal expansion mismatch, so it is currently the most widely used thermal barrier coating material. In addition, the microcracks and pores in the plasma sprayed YSZ coating can become the stress release center, which makes it have better stress tolerance characteristics as a thermal barrier coat...

AI Technical Summary

Problems solved by technology

For example adding CeO 2 , the price change of Ce ions can lead to the generation of a large number of oxygen vacancies, which will promote the diffusion of oxygen to the bonding layer at high temperature, accelerate the oxidation of the bonding layer, and cause the coating to fail; adding La to YSZ 2 o 3 The thermal expansion coefficient of the coating is reduced, thereby reducing the thermal cycle life of the coating, and the phase stability and life of the coating increase with La 2 o 3 decrease with increasing content

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