What Are the Pros and Cons of Ceramic Coils in Vaping Devices?

What are the pros and cons of ceramic coils in vaping devices? In recent years, new materials that play a prominent role in surfaces and interfaces have gained increasing attention. Porous ceramic materials are a new type of material that utilizes physical surfaces, formed through high-temperature sintering, with a three-dimensional network structure containing numerous interconnected pores. This type of porous ceramic material plays a crucial role in the atomization process of electronic cigarettes.

RELX is the first brand in China to use the McWell FEELM heating element in its pod system. The atomization core used by RELX is a ceramic heating element, characterized by stability, high-temperature resistance, and safety in oil conduction, providing a finer taste and leak-proof advantage. Currently, the microporous ceramic atomization core is standard for oil-based electronic cigarettes, used not only by RELX but also by MK electronic cigarettes, NRX, MT, and others. How is this three-dimensional network structure of porous ceramics manufactured?
Porous ceramic materials come in various types, and due to different usage purposes, their performance varies. Therefore, many different preparation techniques have been developed in recent years. The general preparation process for porous ceramics includes granulation, mixing, forming, and sintering.

The main method for forming pores in porous ceramics lies in the formation of voids during the sintering process. Pore-forming methods include adding pore-forming agents, foaming processes, organic foam impregnation processes, and sol-gel processes.

1. Adding Pore-forming Agents

By adding pore-forming agents to the ceramic mixture, these agents occupy a certain space in the green body. During sintering, the pore-forming agents leave the matrix, forming voids and resulting in porous ceramics. The forming methods mainly include molding, extrusion, rolling, isostatic pressing, injection, and slurry casting. The products are generally referred to as honeycomb porous ceramics.

2. Organic Foam Impregnation

Organic foam is impregnated with ceramic slurry, and after drying, the organic foam is burned away, resulting in porous ceramics. This method is suitable for preparing porous ceramics with high porosity and open pores. The products are generally referred to as mesh porous ceramics.

3. Foaming Method

Foaming agents are mixed with clay materials, and under pressure, the clay particles bond together. When sufficient heat reaches the interior of the clay particles, the material foams and expands to fill the mold, cooling to yield porous ceramic materials. Various pore sizes and shapes can be prepared, generally referred to as foam porous ceramics.

4. Sol-Gel Process

Ceramic particles are mixed with organic gel, washed through ion exchange, and then sintered into porous ceramic materials. By adjusting the sintering temperature, the structure, porosity, and pore size of the porous SiO2 material can be altered. The sol-gel method is mainly used to prepare microporous ceramic materials, especially microporous ceramic films.

Advantages

1. Different forming methods can produce complex-shaped products

2. Various pore structures can be created

3. High porosity products can be produced

4. Good sample strength

5. Particularly suitable for producing closed-pore products

6. High porosity and strength

7. Suitable for producing microporous ceramics

8. Suitable for producing film materials

9. Uniform pore distribution

Disadvantages

1. Poor uniformity of pore distribution

2. Not suitable for producing high porosity

3. Cannot manufacture small-diameter closed-pore products

4. Product shapes are limited

5. Product density is difficult to control

6. High requirements for raw materials

7. Process conditions are difficult to control

8. Limited raw materials

9. Low productivity

10. Product shapes are limited

Among the successful applications and active research areas is the addition of volatile or combustible pore-forming agents to the ceramic mixture, utilizing these agents to vaporize or burn out at high temperatures, leaving voids in the ceramic body. Depending on the pore size, ceramics can be classified into coarse pore products ranging from 1000 μm to several tens of micrometers, microporous products ranging from 0.2 to 20 μm, and ultramicroporous products ranging from 0.2 μm to several nanometers. Based on the pore-forming methods and voids, porous ceramics can be classified into: foam ceramics, honeycomb ceramics, and granular ceramics, with corresponding porosity as follows:

The preparation technology allows for precise control of the structure of porous ceramics, including different influences on pore size, shape, and distribution. The bonding strength between aggregate particles determines the strength of the porous ceramics, while also needing to reasonably coordinate the relationship between porosity and strength. #p# Pagination Title #e#

Due to their high porosity, low density, and low thermal conductivity, porous ceramics have significant thermal resistance and low volumetric heat capacity. The applications of porous ceramic materials have spread across metallurgy, chemical engineering, environmental protection, energy, and biology. In addition to the well-known applications in aerospace thermal insulation, missile heads, and filters, they also play a significant role in the electronic cigarette field.

Ceramic atomization cores are currently standard for high-quality pod systems, utilizing a porous ceramic structure with pore sizes generally at the micrometer or sub-micrometer level, commonly referred to as microporous ceramic atomization cores. In addition to atomization cores, there is also a type known as ceramic oil conduction tubes, which also use porous ceramics.

This article is sourced from: "Preparation Technology of Porous Ceramic Materials", edited by Aibang.