Property Comparison Charts
Density (Specific Gravity)
The ratio of a material’s density compared to water (water = 1).
The higher the value, the heavier the material.
Compared to metals, ceramics generally have a density of less than half, making them lightweight materials.
On the other hand, tungsten is heavier than lead and comparable to gold, making it an extremely dense material.
Tungsten is used as a radiation shielding material.
Hardness
Indicates the hardness of a material.
The higher the value, the harder the material.
Compared to general metals, ceramics are extremely hard materials.
Higher hardness means greater resistance to wear.
They are widely used as wear-resistant materials.
Young’s Modulus
The stress required to produce a certain amount of strain.
The higher the value, the greater the stiffness of the material.
Ceramics, tungsten, and molybdenum have higher Young’s modulus than general metals, making them high-stiffness materials.
Fracture Toughness
The resistance of a material to crack propagation.
The higher the value, the more resistant the material is to cracking.
Ceramics are generally brittle and prone to cracking.
However, zirconia has relatively high fracture toughness and exhibits greater resistance to fracture, making it suitable for applications such as knives, scissors, and grinding balls.
Maximum Service Temperature
Usable temperature range
(Varies depending on the environment)
Refractory metals such as tungsten and molybdenum, as well as ceramics, can be used in extremely high-temperature environments.
They are widely used for furnace materials, crucibles, and heat shielding components.
Thermal Shock Resistance
The temperature range a material can withstand under rapid temperature changes.
The higher the value, the more resistant the material is to cracking.
Glass and ceramics are generally prone to cracking under rapid temperature changes.
However, boron nitride, quartz, and silicon nitride offer high thermal shock resistance and are suitable for applications with frequent temperature fluctuations.
Thermal Conductivity
Indicates how easily heat is transferred through a material.
The higher the value, the greater the heat transfer.
Among ceramics, some materials such as aluminum nitride and silicon carbide have high thermal conductivity, while others such as zirconia have low thermal conductivity.
Tungsten and molybdenum also have relatively high thermal conductivity.
Coefficient of Thermal Expansion
Indicates how much a material expands in response to temperature changes.
The higher the value, the more the material expands.
Ceramics, tungsten, and molybdenum have low coefficients of thermal expansion, resulting in minimal deformation due to temperature changes.
Volume Resistivity
Indicates how difficult it is for electricity to pass through a material.
The higher the value, the greater the electrical resistance.
Ceramics are generally poor conductors of electricity and offer excellent electrical insulation.
They are widely used as insulating materials, although some ceramics exhibit electrical conductivity.
Dielectric Constant
A measure of a material’s ability to store electrical energy.
Ceramics are used as insulating materials that can store electrical energy and are widely applied in electronic components.
Corrosion Resistance
The ability of a material to resist degradation in appearance and function due to chemical or biological effects.
Ceramics offer excellent corrosion resistance and are widely used in applications such as artificial bones and corrosion-resistant components.
Tungsten also exhibits strong resistance to acids and alkalis.
Electrical Conductivity
Fine ceramics are generally electrical insulators and do not conduct electricity.
However, some ceramics exhibit semiconducting behavior and can conduct electricity depending on temperature and applied voltage.
Piezoelectricity
Piezoelectric materials generate an electric charge when mechanical stress is applied (direct piezoelectric effect), and conversely, deform when an electric field is applied (inverse piezoelectric effect).
Piezoelectric ceramics are polycrystalline materials, typically lead zirconate titanate (PZT).