Casting Processes: Metal casting processes involve
pouring molten metal into a mold cavity where, once solid, the metal take on
the shape of the cavity. They can be divided into two categories based on the
type of mold:
Expendable Mold Casting: where the mold
must be destroyed in order to remove the part
Permanent Mold Casting: for which the
mold is fabricated out of a ductile material and can be used repeatedly.
Powder Metallurgy: In powder metallurgy
a metal powder is compacted into the desired shape and heated to cause the
particles to bond into a rigid mass.
Deformation Processes: Deformation processes include metal
forming and sheet metalworking processes. These processes use plastic deformation
resulting from the use of a tool that applies stresses to the piece which
exceed the yield stress of the metal. There are two types of deformation processes:
Bulk Processes: Bulk deformation processes
are characterized by large deformations and shape changes and by the fact
that the surface area to volume ratio is relatively small. Bulk processes
include rolling, forging, extrusion and wire and bar drawing.
Sheet Metalworking: Sheet metalworking
processes are performed on metal sheets, strips and coils having a high
surface area to volume ratio. These operations use a punch and die to form
the workpiece. Bending, drawing and shearing are types of sheet metalworking
processes.
Material Removal Processes: These processes remove extra
material from the workpiece in order to achieve the desired shape and include:
Machining Operations: These are cutting
operations using cutting tools that are harder than the metal of the product.
They include turning, drilling, milling, shaping, planing, broaching and
sawing.
Abrasive Machining: In these methods material
is removed by abrasive particles that normally form a bonded wheel. Grinding,
honing and lapping are included in this category.
Nontraditional Processes: These methods
use lasers, electron beams, chemical erosion, electric discharge and electrochemical
energy instead of traditional cutting and grinding tools.
Joining and Assembly Processes:
In these operations multiple parts are connected either permanently or semipermanently
to form a new entity.
Please submit any questions or comments concerning this website to njsalamon@psu.edu.
© by Meghan Henty & N. J. Salamon 1999, 2000. All rights reserved.
Redesigned by William C. Chow 2000.