Macroscopic Properties

Introduction

Macroscopic properties refer to the physical characteristics of a material that can be observed without the aid of a microscope.
These are often the properties most directly related to a material’s use and application.

Mechanical properties define a material’s reactions to mechanical forces, such as strength, ductility, hardness, and toughness.
Strength: Represents the stress that a material can withstand before failure or deformation. Not to be confused with hardness, which refers to a material’s resistance to localized deformation.
Ductility: A measurement of how much a material can deform before breaking under a tensile force. The opposite of this property is brittleness.
Elasticity: A measure of a material’s ability to return to its original size after being distorted. The permanent deformation after removal of stress is referred to as plastic deformation.

Physical properties refer to those measurable characteristics which describe the physical system of a material.
Density: The mass of a material per unit volume. This property often bears upon the weight and hence the usability of a material.
Electrical conductivity: Refers to a material’s ability to conduct electric current. This property is crucial for materials required in electronics or power transmission.
Thermal properties: These indicate how a material behaves under temperature changes. They include thermal conductivity (how well a material transfers heat) and thermal expansion (how a material expands or contracts with temperature changes).

Chemical properties describe how a material behaves when it undergoes a chemical reaction.
Corrosion resistance: Indicates a material’s ability to resist corrosion, that is, the gradual destruction of a material by chemical reactions with its environment.
Reactivity: The likelihood of a material to engage in chemical reactions. Highly reactive materials may be dangerous or difficult to handle, but also may provide useful reactivity in controlled environments.

Optical properties refer to how a material interacts with light.
Transparency: The ability of a material to transmit light without absorption and scattering. Glass is an obvious example of a transparent material.
Refractive index: The measure of how much light is bent, or refracted, when entering a material.