In this article we will answer the following question: “Is Ceramic Flammable?”, and other important questions regarding ceramic production, flammability, toxicity, and other important questions about this highly versatile material.
Is Ceramic Flammable?
No, ceramic is not flammable. Since it’s inorganic, it can’t burn. It doesn’t matter if it’s porcelain, a piece of earthenware, a brick, or a tile, ceramic won’t ignite. Ceramics are produced in ovens that can reach 1000°C, proof that they are willing to sustain heat.
What is ceramic?
Ceramics are usually made from clay minerals. A piece of clay or clay-like product is shaped and fired to produce a resistant material.
Ceramic presents crystallinity, is a good thermal and electrical insulator.
Some history of ceramics
Due to the high durability of ceramics, pottery and ceramic shards can survive for many centuries in archeological sites.
The oldest known pottery dates from about 30.000 years ago, during the Old Stone age, and is called “Venus of Dolní Věstonice”.
The oldest form of ceramic didn’t serve practical uses, but cultural.
For comparison, pottery has begun 18 thousand years before agriculture.
Early pottery was made according to the clay supply available in each region. Pottery was discovered independently in various regions of the planet across the centuries.
The applications of Ceramics are numerous.
When the word “ceramics” comes to our minds the first thing we think about is pottery, but many other common or high-tech applications are there. Let’s look at a few examples:
- Structural components such as bricks, pipes, floor, and tiles.
- Refractory materials: often used when resistance to decomposition is required, because of intense heat, pressure, or chemicals. Refractories can maintain their form and properties even after some extreme conditions.
- Ballistic protection and vehicle armor.
- High-tech medical implant devices.
- Ceramic matrix composites that, unlike common ceramics, can handle thermal shocks.
- Ceramic discs in high-performance cars and heavy vehicles.
- Some protections in spaceships, like some in the Space Shuttle program.
- Kitchen utensils like knife blades.
- Ceramic bearing balls are corrosion resistant and barely require lubrification.
- Parts of gas turbine engines.
- High-tech watchmaking.
- Kitchen appliances.
Ceramic production and chemistry
Ceramic is a non-metallic, inorganic, nitride, or carbide, composed mostly of (inorganic) carbon and silicon.
Ceramics are very durable and can sustain a lot of heat, and many forms of physical and chemical corrosion, depending on the type of ceramic.
It’s hard to assume general properties for ceramics, but at least a few can be pointed out: high hardness, low conductivity, and high melting point.
To produce a ceramic, basically what you have to do is to cook a piece of clay.
When the product is heated, several inorganic chemical reactions take place as a result of the scaping of the water molecules. As a result, a crystalline structure is strongly bonded.
Once the crystalline network is formed, irreversible chemical reactions had happened. As a result, hardness appears.
Vitrification can also be applied in ceramics. A glass-like layer made of silicons can be chemically attached to the product in the last stages of production.
As a result, the final product acquires a shiny aspect, and some physical properties like resistance to scratching can be enhanced.
The explanation for the hardness ceramics presents is the same as the toughness any rock, salt, or many other inorganic materials have: their chemical bonds.
The picture above is an example of how inorganic silicon-based structures could appear atomically. You can consider that the picture is a photo that was taken from a top view.
To have a more realistic overview, imagine other (exact) layers coming out of your screen, firmly bonded to each other. This is only possible in ionic bonds.
In chemistry, when a chemical bond occurs it changes the properties of the material. If a bond is strong enough and is made geometrically, a crystalline network is formed.
Ceramics are inert materials built at a high temperature above 1000°C. The material is non-combustible, it’s not made of organic compounds so it can’t burn.
Ceramics are fire-resistant materials that sustain heat from 1000 to 1600°C.
Even though ceramics can sustain a good amount of heat, they can’t endure abrupt changes in temperature.
If you take porcelain to the oven, heat it at max temperature, and then put cold water directly on it, it would probably see cracking. This happens because the chemical bonds in its crystalline structure can slightly move at once, breaking the network.
Ceramic is considered inert, but toxicity may arise from chronic exposure to its starting materials and by-products.
Ceramics comprehends a wide class of materials, but the most common are porcelain, earthenware, and construction materials. Ceramics are inorganic materials, non-flammable, and good electrical isolators.
Ceramics can withstand a lot of heat but can’t sustain sudden temperature changes.
Frequently Asked Questions: “Is Ceramic Flammable?
Is ceramic tile flammable?
No. Like other ceramics, ceramic tiles do not contain organic compounds, so they can’t ignite. In fact, these tiles are considered fire-resistant. But an abrupt variation of temperature could induce the ceramic to crack.
Can ceramic melt?
Yes. If enough heat is provided, the strong ionic bond within the structure of ceramic could start to crumble. Luckily, this won’t happen unless a temperature around 1000°C is reached.
Is brick flammable?
No. Modern fired clay bricks are not flammable. They are inorganic materials that are considered fire-resistant materials, just like other forms of ceramic, cement, and concrete.
Are ceramics combustible?
For a material to be considered combustible under normal circumstances, it must be an organic compound, mostly composed of hydrocarbon (carbon and hydrogen-based molecules).
Ceramics are inorganic materials that, virtually, can’t be burned. But they can melt under extreme heating around 1000°C. Also, ceramics can still conduct heat, but less.
Refractory ceramics, although, are very good heat insulators that are used for many applications, like high-performance ovens.
Why are ceramics heat resistant?
This phenomenon happens because their molecules can’t expand, so heat can’t easily travel through the ionic structure.
What temperature do ceramic cracks?
It depends on the ceramic constitution and size. Around 1000°C is about enough to see some change in the crystalline structure.
Temperature alone isn’t a good way to determine how ceramic can crack thermally.
When we say that certain material has a specific temperature, it’s only an approximate value. The surface of the material normally acquires a higher temperature than an inner point.
This difference could be enough for the structure present cracklings before the melting or flashing point.
Does ceramic conduct electricity?
Under normal circumstances, ceramic is a poor electricity conductor, that’s why it’s used as an isolator.
This happens because the ionic structure of the ceramic is very concise and doesn’t have “free electrons” that promulgate electricity.
But certain ceramics under specific conditions can act as semiconductors and can present superconductivity and Piezoelectricity.
A ceramic plate or tile will never conduct electricity under mild conditions unless they have something else added to it, like a metallic ornament.
Can ceramics go in the microwave?
Normally, yes. It’s always safer to check the fabricant’s instructions first. Porcelain goods can easily go to the microwave unless they have paint, metal, or another kind of ornament.
The more clay-like a piece of ceramic is, the more water it has, so it might suffer from some cracking.
The microwave’s basic function is to vibrate water molecules, so the remaining water within a ceramic could be a problem upon heating.
Are ceramic tiles heat resistant?
Yes, they are. Just like other ceramics. But they not necessarily are heat-proof.
Is ceramic fireproof?
Normally, yes. Ceramics can withstand a lot of fire before changing their properties.
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Danzer, R., Lube, T., Supancic, P., & Damani, R. (2008). Fracture of Ceramics. Advanced Engineering Materials, 10(4), 275–298. doi:10.1002/adem.200700347