What Is a Ceramic Adhesive?
Ceramic adhesives are adhesives that do not contain any organic materials and are based on fine ceramics.
They are widely used for bonding ceramics to each other, ceramics to metals, and for coating and screw loosening. They are also able to maintain their adhesive strength in high-temperature environments while retaining their unique properties of heat resistance.
Furthermore, new applications, such as bonding semiconductor components, are increasing. Therefore, it can be said that this is an epoch-making adhesive that is expected to expand its applications in the future.
Uses of Ceramic Adhesives
Ceramic adhesives are used in a wide variety of applications due to their special properties. They can be used primarily for bonding ceramics to each other or between ceramics and other metals, or as coatings.
One example is their use as a coating to protect the aluminum panels of spacecraft from X-rays.
In space, the hull is constantly exposed to intense X-rays and cosmic rays due to the lack of protection provided by the Earth’s atmosphere, but ceramic adhesives can provide an effective layer of protection even in such a harsh environment.
Principle of Ceramic Adhesives
There are two main forms of ceramic adhesives, one-component and mixed-liquid, and the appropriate form is chosen for each application environment and condition.
1. One-Component Type
This is a liquid adhesive that can be applied directly. It is commonly used to bond ceramics to each other or ceramics to other metals.
2. Mixed-Liquid Type
In this form, the powder is mixed with a hardener (or water). This type is often used primarily in special coating applications, such as protecting aluminum panels on spacecraft from X-rays.
A unique feature of ceramic adhesives is that they can be used at very high temperatures. Depending on the material, their heat resistance temperatures can theoretically be up to 2,800°C.
In addition, there are four main categories of intended use: general purpose adhesion, adhesion of special materials, repair, and sealing applications. For each of these purposes, the selection of an appropriate ceramic adhesive is an important factor.
Types of Ceramic Adhesives
There are two main types of ceramic adhesives: one-component and mixed-component. They differ according to the form, properties, and application environment of the adhesive.
1. One-Component Type
One-component adhesives are, as the name implies, adhesives consisting of one component. They can be applied directly and are commonly used to bond ceramics to each other or ceramics to other metals.
2. Mixture Type
Mixture type adhesives are made by mixing a powder with a hardener (or water). This type of adhesive is especially suited for use in high heat or harsh environments and is used for special applications, such as protecting aluminum panels on spacecraft from X-rays.
How to Select a Ceramic Adhesive
When selecting a ceramic adhesive, you should consider the following
1. Intended Use
It is most important to define what the adhesive will be used for. The type of adhesive depends on its intended use. For example, one-component adhesives are suitable for bonding ceramic to ceramic or ceramic to other metals, while mixed-component adhesives are suitable for special coating applications.
2. Environmental Conditions
The environment in which the adhesive will be used must be considered. For example, environments with high heat or exposure to chemicals require adhesives that can withstand these conditions.
3. Heat Resistance
Ceramic adhesives can be used in environments with very high temperatures, but the heat resistance of each product will vary. Therefore, it is necessary to select a product that is compatible with the temperature range in which it will be used.