Composite thermal insulation coating for ct tube liquid metal bearing and preparation method thereof

Abstract

The invention discloses a composite heat-insulating coating for a CT ball tube liquid metal bearing and a preparation method thereof, belonging to the technical field of composite heat-insulating coatings. Using carbon fiber, nano-titanium dioxide, quartz chopped fiber, aluminum hydroxide and phosphoric acid as the main raw materials, the carbon fiber is first subjected to ball milling and low-temperature plasma etching, and then the quartz chopped fiber is subjected to fiber dissociation treatment, and carbon fiber-nano titanium dioxide is prepared ‑Quartz chopped fiber‑aluminum phosphate coating mixed slurry, and then the coating mixed slurry is smeared on the metal substrate, and finally through gradient heat treatment, the carbon fiber‑nano titanium dioxide‑quartz chopped fiber‑aluminum phosphate composite thermal insulation coating is prepared. The invention has the advantages of simple operation and low cost. The composite thermal insulation coating prepared by the invention has the advantages of excellent high temperature resistance and thermal insulation performance, high strength, light weight and long service life, and has no air-porous layer design, is suitable for high vacuum environment, and is suitable for the thermal insulation field of CT tube liquid metal bearing. It has a good prospect of engineering application.

Description

technical field [0001] The invention relates to a preparation method of a composite thermal insulation coating for a CT tube liquid metal bearing, in particular to a preparation method of a carbon fiber-nano titanium dioxide-quartz chopped fiber-aluminum phosphate composite thermal insulation coating, which belongs to a composite insulation coating. The field of thermal coating technology. Background technique [0002] As a kind of X-ray clinical diagnostic equipment, CT (Computed Tomography) has become a necessary equipment in hospitals, and it has important social and economic significance to protect people's health. CT tube is the X-ray emitting device in CT, which belongs to the key part of CT. The CT tube usually contains components such as rotating anode, filament, glass bulb, etc. The performance and life of the rotating anode have an important influence on the performance and life of the CT tube. The rotating anode of the CT tube consists of a bearing, a target dis...

AI Technical Summary

Problems solved by technology

Although the above patents have many advantages, because the working environment of the CT ball bearing is high vacuum, and the above-mentioned coatings contain many pores, air is easy to store in the pores, making it difficult for the CT tube to reach a high vacuum state; and in CT During the working process of the tube, the pores in the coating are prone to continuous outgassing, which will destroy the high vacuum environment inside the CT tube, so the coatings disclosed in the above patents are not suitable for CT tube bearings.

[0004] Patent CN 111117475 A proposes an ablation-resistant thermal insulation coating comprising silicone resin, ceramic precursor and organometallic salt and its preparation method, wherein the organometallic salt is hydrolyzed during the polymerization reaction of silicone resin and ceramic precursor Metal complexes are formed, and the metal complexes are evenly distributed in the three-dimensional network formed by the polymerization of silicone resin and ceramic precursors, forming an ablation-resistant and heat-shielding coating with uniform components, and the performance of the coating in all directions is uniform, both It ensures the effect of anti-ablation and heat insulation of the coating, and overcomes the disadvantage of uneven mixing of components, but the bonding force between this coating and the metal substrate is relatively weak, so it is not suitable for CT ball bearings

Patent CN 111116166 A proposes a method for preparing a heat-insulating and anti-corrosion coating on the surface of concrete. The coating includes phosphate adhesive, metal hydroxide, calcium oxide compound, nano-alumina, etc. The heat-insulating and anti-corrosion coating on the concrete surface can be It solidifies into a film and has a good bonding effect with concrete, but the coating has poor bonding with metal, so it is not suitable for surface heat insulation treatment of CT ball bearings

[0005] Aluminum phosphate has a high melting point and low density. It is an inorganic compound with excellent high temperature resistance and heat insulation performance. It is suitable as a matrix material for composite heat insulation coatings; however, aluminum phosphate has the disadvantages of relatively poor mechanical properties and toughness. Adding other materials to improve the mechanical properties and toughness of aluminum phosphate, aluminum phosphate coating has practical value