List of materials properties facts for kids

A material property is a special feature of a material that doesn't change no matter how much of the material you have. Think of it like a material's unique superpower! These properties help us compare different materials and choose the best one for a specific job, like building a bridge or making a phone.

Sometimes, a material property has a fixed value, like the melting point of ice. We call these material constants. It's important not to confuse them with physical constants, which are universal values found everywhere in the universe.

A material's property can also change depending on things like temperature. For example, some materials become softer when they get hot. Also, some materials act differently depending on the direction you measure them in. This is called anisotropy.

Scientists and engineers use these properties to predict how a material will behave in real-world situations. They measure these properties using special, agreed-upon tests. Many of these tests are documented by groups like ASTM International.

Sound Properties: How Materials Handle Noise

• Acoustical absorption: How well a material soaks up sound, making a room quieter.
• Speed of sound: How fast sound travels through a material. Sound travels faster through solids than through air.
• Sound reflection: How much sound bounces off a material. Hard, smooth surfaces reflect more sound.

Tiny Atom Properties: What Atoms Are Like

• Atomic mass: This is the average weight of an atom of an element. It's measured in units called daltons (Da).
• Atomic number: This tells you how many protons are in the center (nucleus) of an atom. Every element has a unique atomic number.

Chemical Properties: How Materials React

• Corrosion resistance: How well a material can resist damage from chemical reactions, like rust forming on metal.
• Hygroscopy: How much a material attracts and holds water from the air.
• pH: This measures how acidic or basic a material is.
• Reactivity: How easily a material takes part in chemical reactions with other substances.
• Surface tension: The "skin" on the surface of a liquid that makes it resist outside forces. Think of a water strider walking on water!

Electric Properties: How Materials Handle Electricity

• Electrical resistivity and conductivity: How easily electricity can flow through a material. Conductors (like copper) let electricity flow easily, while insulators (like rubber) resist it.
• Dielectric strength: How much electric force a material can handle before it breaks down and lets electricity pass through.
• Permittivity: How well a material can store electrical energy when an electric field is applied.
• Piezoelectric constants: These describe materials that can create an electric charge when squeezed or stretched, or change shape when an electric field is applied.

Magnetic Properties: How Materials React to Magnets

• Curie temperature: The temperature at which a material loses its permanent magnetic properties.
• Permeability: How easily a material can become magnetized or allow magnetic fields to pass through it.
• Hysteresis: This describes how a material's magnetic properties depend on its past magnetic history.

Making Things Properties: How Easy Materials Are to Work With

• Castability: How easily a material can be melted and poured into a mold to create a good quality shape.
• Machinability rating: How easy it is to cut, drill, or shape a material using tools.

Mechanical Properties: How Materials Handle Forces

• Brittleness: This is how easily a material breaks or shatters without bending much when a force is applied. Think of glass or concrete.
• Bulk modulus: This measures how much a material resists being squeezed from all sides.
• Compressive strength: The maximum force a material can withstand before it breaks when being pushed or squeezed.
• Creep: The slow, gradual change in shape of a material over time, especially when under constant stress or at high temperatures.
• Density: How much "stuff" is packed into a certain amount of space in a material. It's mass per unit volume.
• Ductility: The ability of a material to be stretched or pulled into a thin wire without breaking. Copper is a very ductile metal.
• Durability: How well a material can last and resist wear, pressure, or damage over time.
• Elasticity: The ability of a material to return to its original shape after being stretched or squeezed. A rubber band is elastic.
• Fatigue limit: The maximum stress a material can handle repeatedly without breaking.
• Hardness: How well a material resists being scratched or dented on its surface. Diamonds are very hard.
• Malleability: The ability of a material to be hammered or pressed into thin sheets without cracking. Aluminum foil is a good example of a malleable material.
• Plasticity: The ability of a material to change shape permanently without breaking. This is the opposite of brittleness.
• Poisson's ratio: This describes how much a material gets thinner when it's stretched.
• Resilience: The ability of a material to absorb energy when it's bent or stretched and then spring back.
• Shear strength: The maximum force a material can withstand before it breaks when being twisted or cut.
• Tensile strength: The maximum force a material can withstand before it breaks when being pulled apart.
• Toughness: The ability of a material to absorb energy and bend or deform without breaking when hit or stressed. A tough material can handle shocks.
• Viscosity: This describes how thick or "gooey" a fluid is, or how much it resists flowing. Honey has high viscosity.
• Yield strength: The point at which a material starts to permanently change shape when a force is applied.
• Young's modulus: This measures how stiff a material is. A high Young's modulus means the material is very stiff and hard to stretch.

Light Properties: How Materials Handle Light

• Color: How a material reflects or absorbs different wavelengths of light.
• Reflectivity: How much light bounces off the surface of a material. A mirror has high reflectivity.
• Refractive index: How much a material bends light as it passes through it. This is why a straw in a glass of water looks bent.
• Transmittance: How much light passes through a material. Clear glass has high transmittance.

Heat Properties: How Materials Handle Temperature

• Boiling point: The temperature at which a liquid turns into a gas.
• Coefficient of thermal expansion: How much a material expands or shrinks when its temperature changes.
• Melting point: The temperature at which a solid turns into a liquid.
• Thermal conductivity: How well a material allows heat to flow through it. Metals are good thermal conductors.
• Thermal expansion: The tendency of matter to change in volume in response to a change in temperature.
• Specific heat capacity: How much heat energy is needed to raise the temperature of a certain amount of a material.

See also

In Spanish: Propiedades mecánicas de los materiales para niños

• Physical property
• Strength of materials