In
metalworking
Metalworking is the process of shaping and reshaping metals in order to create useful objects, parts, assemblies, and large scale structures. As a term, it covers a wide and diverse range of processes, skills, and tools for producing objects on e ...
, forming is the fashioning of metal parts and objects through mechanical
deformation; the
workpiece
A workpiece is a piece, often made of a single material, that is being processed into another desired shape (such as building blocks).
The workpiece is usually a piece of relatively rigid material such as wood, metal, plastic, or stone. After a ...
is reshaped without adding or removing material, and its mass remains unchanged. Forming operates on the
materials science
Materials science is an interdisciplinary field of researching and discovering materials. Materials engineering is an engineering field of finding uses for materials in other fields and industries.
The intellectual origins of materials sci ...
principle of
plastic deformation, where the physical shape of a material is permanently deformed.
Characteristics
Metal forming tends to have more uniform characteristics across its subprocesses than its contemporary processes,
cutting
Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force.
Implements commonly used for wikt:cut, cutting are the knife and saw, or in medicine and science the sca ...
and
joining.
On the industrial scale, forming is characterized by:
* Very high loads and
stresses required, between 50 and ()
* Large, heavy, and expensive machinery in order to accommodate such high stresses and loads
* Production runs with many parts, to maximize the economy of production and compensate for the expense of the machine tools
Forming processes
Forming processes tend to be categorised by differences in effective stresses. These categories and descriptions are highly simplified, since the stresses operating at a local level in any given process are very complex and may involve many varieties of stresses operating simultaneously, or it may involve stresses which change over the course of the operation.
Compressive forming involves those processes where the primary means of plastic deformation is uni- or multiaxial compressive loading.
*
Rolling
Rolling is a Motion (physics)#Types of motion, type of motion that combines rotation (commonly, of an Axial symmetry, axially symmetric object) and Translation (geometry), translation of that object with respect to a surface (either one or the ot ...
, where the material is passed through a pair of rollers
*
Extrusion
Extrusion is a process used to create objects of a fixed cross section (geometry), cross-sectional profile by pushing material through a Die (manufacturing), die of the desired cross-section. Its two main advantages over other manufacturing pro ...
, where the material is pushed through an orifice
*
Die forming, where the material is
stamped by a
press around or onto a die
*
Forging
Forging is a manufacturing process involving the shaping of metal using localized compression (physics), compressive forces. The blows are delivered with a hammer (often a power hammer) or a die (manufacturing), die. Forging is often classif ...
, where the material is shaped by localized compressive forces
*Indenting, where a tool is pressed into the workpiece
Tensile forming
Tensile forming involves those processes where the primary means of plastic deformation is uni- or multiaxial tensile stress.
*Stretching, where a tensile load is applied along the longitudinal axis of the workpiece
*Expanding, where the circumference of a hollow body is increased by tangential loading
*Recessing, where depressions and holes are formed through tensile loading
Combined tensile and compressive forming
This category of forming processes involves those operations where the primary means of plastic deformation involves both tensile stresses and compressive loads.
*Pulling through a die
*
Tandem rolling mill
*
Deep drawing
*
Spinning
Spin or spinning most often refers to:
* Spin (physics) or particle spin, a fundamental property of elementary particles
* Spin quantum number, a number which defines the value of a particle's spin
* Spinning (textiles), the creation of yarn or thr ...
*
Flange
A flange is a protruded ridge, lip or rim (wheel), rim, either external or internal, that serves to increase shear strength, strength (as the flange of a steel beam (structure), beam such as an I-beam or a T-beam); for easy attachment/transfer o ...
forming
*Upset bulging
Bending
This category of forming processes involves those operations where the primary means of plastic deformation is a bending load.
Shearing
This category of forming processes involves those operations where the primary means of plastic deformation is a shearing load.
Notes
References
*
See also
*The
Forming section of
List of manufacturing processes
This tree lists various manufacturing processes arranged by similarity of function.
Casting
*Bellfounding
*Centrifugal casting (industrial)
*Continuous casting
*Die casting
*Evaporative-pattern casting
**Full-mold casting
**Lost-foam castin ...
*
Ferrous metallurgy
Ferrous metallurgy is the metallurgy of iron and its alloys. The earliest surviving prehistoric iron artifacts, from the 4th millennium BC in Egypt, were made from meteoritic iron-nickel. It is not known when or where the smelting of iron from ...
*
Moulding
*
Pressing
{{Authority control
Metalworking
Metal forming