Glossary of mechanical engineering

Glossary of Mechanical Engineering

Mechanical engineering is a diverse field that applies principles of physics and materials science for analysis, design, manufacturing, and maintenance of mechanical systems. This glossary provides definitions and explanations of key terms and concepts in mechanical engineering.

A

Actuator

An actuator is a device that converts energy into motion. It is used in mechanical systems to move or control a mechanism or system. Actuators can be powered by electric current, hydraulic fluid pressure, or pneumatic pressure.

Alloy

An alloy is a mixture of two or more elements, where at least one is a metal. Alloys are designed to have specific properties, such as increased strength or resistance to corrosion.

B

Bearing

A bearing is a machine element that constrains relative motion to only the desired motion and reduces friction between moving parts. Bearings are classified based on the type of operation, the motions allowed, or the directions of the loads (forces) applied to the parts.

Boiler

A boiler is a closed vessel in which water or other fluid is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.

C

CAD (Computer-Aided Design)

Computer-Aided Design (CAD) is the use of computer systems to assist in the creation, modification, analysis, or optimization of a design. CAD software is used to increase the productivity of the designer, improve the quality of design, and create a database for manufacturing.

CAM (Computer-Aided Manufacturing)

Computer-Aided Manufacturing (CAM) is the use of software and computer-controlled machinery to automate a manufacturing process. CAM is used in conjunction with CAD to streamline the manufacturing process.

D

Dynamics

Dynamics is the branch of mechanics concerned with the motion of bodies under the action of forces. It is divided into kinematics, which describes motion without regard to its causes, and kinetics, which relates motion to its causes.

E

Efficiency

Efficiency in mechanical systems is the ratio of the useful output of a system to the input, expressed as a percentage. It is a measure of how well a system converts energy into work.

Engine

An engine is a machine designed to convert one form of energy into mechanical energy. Heat engines, such as internal combustion engines, burn a fuel to create heat, which is then used to do work.

F

Fatigue

Fatigue is the weakening of a material caused by repeatedly applied loads. It is a progressive and localized structural damage that occurs when a material is subjected to cyclic loading.

Fluid Mechanics

Fluid Mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them. It has applications in a wide range of disciplines, including mechanical engineering.

G

Gear

A gear is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part to transmit torque. Gears are used to change the speed, torque, and direction of a power source.

H

Heat Exchanger

A heat exchanger is a device used to transfer heat between two or more fluids. Heat exchangers are used in both cooling and heating processes.

I

Injection Molding

Injection Molding is a manufacturing process for producing parts by injecting molten material into a mold. It is commonly used for plastics but can also be used for metals and glass.

J

Joule

The joule is a derived unit of energy in the International System of Units. It is equal to the energy transferred when a force of one newton acts on an object in the direction of the force's motion through a distance of one meter.

K

Kinematics

Kinematics is the study of motion without considering the forces that cause it. It is a branch of mechanics that describes the motion of points, bodies, and systems of bodies.

L

Lathe

A lathe is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, knurling, drilling, or deformation.

M

Machining

Machining is a process in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process. It is a part of the manufacturing process.

N

Newton

The newton is the International System of Units (SI) derived unit of force. It is named after Isaac Newton in recognition of his work on classical mechanics.

O

Oscillation

Oscillation is the repetitive variation, typically in time, of some measure about a central value or between two or more different states.

P

Pump

A pump is a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action. Pumps operate by some mechanism (typically reciprocating or rotary), and consume energy to perform mechanical work by moving the fluid.

Q

Quenching

Quenching is a rapid cooling process used in metallurgy to harden steel. It involves heating the metal to a high temperature and then cooling it quickly in water, oil, or air.

R

Robotics

Robotics is an interdisciplinary branch of engineering and science that includes mechanical engineering, electrical engineering, computer science, and others. It deals with the design, construction, operation, and use of robots.

S

Stress

Stress in mechanics is the internal force per unit area that resists a change in shape or size of a body. It is a measure of the intensity of the internal forces acting within a deformable body.

T

Thermodynamics

Thermodynamics is the branch of physics that deals with the relationships between heat and other forms of energy. It describes how thermal energy is converted to and from other forms of energy and how it affects matter.

U

Ultrasonics

Ultrasonics refers to the application of ultrasound, which is sound waves with frequencies higher than the upper audible limit of human hearing. It is used in various industrial and medical applications.

V

Viscosity

Viscosity is a measure of a fluid's resistance to deformation at a given rate. It describes the internal friction of a moving fluid.

W

Welding

Welding is a fabrication process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint.

X

X-ray Diffraction

X-ray Diffraction (XRD) is a tool used for identifying the atomic and molecular structure of a crystal, in which the crystalline atoms cause a beam of incident X-rays to diffract into many specific directions.

Y

Yield Strength

Yield Strength is the stress at which a material begins to deform plastically. Before the yield point, the material will deform elastically and will return to its original shape when the applied stress is removed.

Z

Zero Point Energy

Zero Point Energy is the lowest possible energy that a quantum mechanical physical system may have. Unlike in classical mechanics, quantum systems constantly fluctuate in their lowest energy state due to the Heisenberg uncertainty principle.