机械外文资料

Mechanical engineering

Mechanical engineers design and build

engines

and

power plants

...

...

structures

and

vehicles

of all sizes.

Mechanical engineering

is a discipline of

engineering

that applies the principles

of

physics

and

materials science

for analysis, design,

manufacturing

, and maintenance

of

mechanical

systems

. It is the branch of engineering that involves the production and usage

of

heat

and mechanical power for the design, production, and operation of

machines

and

tools

. It is

one of the oldest and broadest

engineering disciplines

.

The engineering field requires an understanding of core concepts

including mechanics, kinematics, thermodynamics, materials science, and structural analysis.

Mechanical engineers use these core principles along with tools like computer-aided

engineering and product lifecycle management to design and analyze manufacturing plants,

industrial equipment and machinery, heating and cooling

systems,transport systems, aircraft, watercraft, robotics, medical devices and more.

Mechanical engineering emerged as a field during the industrial revolution in Europe in the

18th century; however, its development can be traced back several thousand years around the

world. Mechanical engineering science emerged in the 19th century as a result of developments in

the field of physics. The field has continually evolved to incorporate advancements in technology,

and mechanical engineers today are pursuing developments in such fields

as composites, mechatronics, and nanotechnology. Mechanical engineering overlaps

with aerospace engineering, civil engineering, electrical engineering, petroleum engineering,

and chemical engineering to varying amounts.

Development

Applications of mechanical engineering are found in the records of many ancient and

medieval societies throughout the globe. In

ancient Greece

, the works of

Archimedes

(287 BC

–

212

BC) deeply influenced mechanics in the Western tradition and

Heron of Alexandria

(c. 10

–

70 AD)

created the first steam engine. In

China

,

Zhang Heng

(78

–

139 AD) improved a

water clock

and

invented a

seismometer

, and

Ma Jun

(200

–

265 AD) invented a chariot with

differential

gears. The

medieval Chinese horologist and engineer

Su Song

(1020

–

1101 AD) incorporated

an

escapement

mechanism into his

astronomical

clock tower

two centuries before any escapement

can be found in clocks of medieval Europe, as well as the world's first known endless

power-transmitting

chain drive

.

During the years from 7th to 15th century, the era called the

Islamic Golden Age

, there were

remarkable contributions from

Muslim inventors

in the field of mechanical technology.

Al- Jazari

,

who was one of them, wrote his famous

Book of Knowledge of Ingenious Mechanical Devices

in

1206, and presented many mechanical designs. He is also considered to be the inventor of such

mechanical devices which now form the very basic of mechanisms, such as

the

crankshaft

and

camshaft

.

Important breakthroughs in the foundations of mechanical engineering occurred in England

during the 17th century when

Sir Isaac Newton

both formulated the three

Newton's Laws of

Motion

and developed

Calculus

. Newton was reluctant to publish his methods and laws for years,

but he was finally persuaded to do so by his colleagues, such as

Sir Edmund Halley

, much to the

benefit of all mankind.

During the early 19th century in

England

,

Germany

and

Scotland

, the development of

machine tools led mechanical engineering to develop as a separate field within engineering,

providing manufacturing machines and the engines to power them.

]

The first British professional

society of mechanical engineers was formed in 1847

Institution of Mechanical Engineers

, thirty

years after the civil engineers formed the first such professional society

Institution of Civil

Engineers

. On the European continent,

Johann Von Zimmerma nn

(1820

–

1901) founded the first

factory for grinding machines in Chemnitz (Germany) in 1848.

In the United States, the American Society of Mechanical Engineers (ASME) was formed in

1880, becoming the third such professional engineering society, after the American Society of Civil

Engineers (1852) and the American Institute of Mining Engineers (1871). The first schools in the

United States to offer an engineering education were theUnited States Military Academy in 1817,

an institution now known as Norwich University in 1819, and Rensselaer Polytechnic Institute in

1825. Education in mechanical engineering has historically been based on a strong foundation in

mathematics and science.

Education

Degrees in mechanical engineering are offered at universities worldwide. In Brazil,

Ireland, Philippines, China, Greece, Turkey, North America, South Asia, India and the United

Kingdom, mechanical engineering programs typically take four to five years of study and result

in a

Bachelor of Science

(), Bachelor of Science Engineering (),

Bachelor of

Engineering

(),

Bachelor of Technology

(), or

Bachelor of Applied

Science

() degree, in or with emphasis in mechanical engineering. In Spain, Portugal

and most of South America, where neither BSc nor BTech programs have been adopted, the

formal name for the degree is

six years of training. In Italy the course work is based on five years of training, but in order to

qualify as an Engineer you have to pass a state exam at the end of the course.

In Australia, mechanical engineering degrees are awarded as Bachelor of Engineering

(Mechanical). The degree takes four years of full time study to achieve. To ensure quality in

engineering degrees, the Australian Institution of Engineers accredits engineering degrees

awarded by Australian universities. Before the degree can be awarded, the student must

complete at least 3 months of on the job work experience in an engineering firm. Similar

systems are also present in South Africa and are overseen by the Engineering Council of

South Africa (ECSA).

In the United States, most undergraduate mechanical engineering programs

are

accredited by the Accreditation Board for Engineering and Technology (ABET) to ensure

similar course requirements and standards among universities. The ABET web site lists 276

accredited mechanical engineering programs as of June 19, 2006.

Mechanical engineering

programs in Canada are accredited by the Canadian Engineering Accreditation Board

(CEAB),

and most other countries offering engineering degrees have similar accreditation

societies.

Coursework

Standards set by each country's accreditation society are intended to provide uniformity

in fundamental subject material, promote competence among graduating engineers, and to

maintain confidence in the engineering profession as a whole. Engineering programs in the

U.S., for example, are required by ABET to show that their students can

both thermal and mechanical systems areas.

however, may differ from program to program. Universities and

Institutes of technology

will