Buffer coating for trough type solar thermal power generation

Abstract

The invention relates to a buffer coating for trough type solar thermal power generation, which can be coated on the surface of a stainless steel metal matrix. The buffer coating is a TiCrNiFeY coating formed by Ti, Cr, Ni, Fe and Y, wherein the content of Ti is 10.5-22.5wt%; the content of Cr is 7.2-12.5wt%; the content of Ni is 3.6-7.5wt%; the content of Y is 1.2-2.5wt%; and the balance is Fe. Favorable adhesive property is provided between the buffer coating provided by the invention and the stainless steel matrix, and the buffer layer has excellent oxidation and thermal cycling stress resisting capabilities, so that the corrosion and fall problems between the metal matrix and functional coatings are effectively solved and the service life of the solar functional coatings is prolonged.

Description

technical field [0001] The invention belongs to the technical field of solar power generation, and more specifically, the invention relates to a buffer coating for trough solar thermal power generation. Background technique [0002] Solar thermal power generation is an important technical approach for large-scale development and utilization of solar energy. At present, there are tower, trough, and dish systems, among which trough and tower systems are more commercially used, especially trough solar thermal power generation, which is the most popular so far. So far, it is the only mature technology in the world that has been commercialized for 20 years, and its cost is much lower than that of photovoltaic power generation. [0003] The energy storage system of the trough-type concentrating thermal power generation system can realize 24-hour operation. With the increase of scale, the cost of power generation is also very competitive. In medium and high temperature heat collec...

AI Technical Summary

Problems solved by technology

However, under high temperature conditions, because its infrared emissivity increases significantly with the rise of temperature, under the constant thermal shock between the metal substrate (such as stainless steel) and the solar functional coating, cracks will appear on the surface of the functional coating, and even The separation between the coating and the substrate allows the metal ions in the functional coating to diffuse or infiltrate into the metal substrate and react

The main reason for this phenomenon is that the matching between the coating material and the substrate is poor, especially the difference between the thermal expansion coefficient is large, the coating is very prone to stress cracking or peeling, and it is difficult to meet the long life of the substrate. The use requirements usually solve the problem of cracks and peeling of the coating due to the difference in thermal expansion performance. The method of spraying a buffer transition layer with a coefficient of thermal expansion between the buffer coating and the substrate is mainly used.