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(which includes rolling, extrusion, and drawing) and workpieces and
machine parts manufacturing.
11)
forging, forgings.
Forging is one of the oldest metalworking processes
during which forgings are produced.
12)
open die forging, impression die forging, closed die forging.
Workpieces
and machine parts manufacturing
embraces open die forging, impres-
sion die forging, closed die forging, etc.
13)
to improve.
Forging improves the mechanical properties of metals.
14)
grain.
Forging minimizes the internal grain size in metal.
15)
drawing out, upsetting, squeezing.
There are different kinds of forging
operations: drawing out, upsetting, squeezing in compression dies.
16)
cross section.
While drawing out the workpiece length increases and its
cross section decreases.
17)
die.
Most forging operations use metal-forming dies.
18)
to withstand.
Metal-forming dies must be precisely designed and care-
fully heat-treated to withstand the tremendous forces and pressure.
19)
flat, shaped.
Open die forging uses flat and shaped dies.
20)
to achieve.
On
completing open die forging, forgings require their
considerable machining to achieve the final shape.
21)
to attach to the anvil.
In impression die forging, the metal workpiece is
placed in a die which is attached to the anvil.
22)
to drop.
The hammer is dropped on the
workpiece to make the metal
flow and fill the die cavities.
23)
excess metal, flash.
Excess metal flows out of the die and forms flash.
24)
to prevent from.
The flash cools more rapidly than the rest of material
so it helps prevent from forming more flash.
25)
lubrication.
The disadvantage of closed die forging is the need for bet-
ter lubrication and workpiece placement.
26)
sheet metal forming.
Sheet metal forming is one of the manufacturing
processes.
27)
stamping, punching, bending.
Sheet metal forming includes stamping,
punching, bending, etc.
28)
to involve.
Recent developments involve the heating of dies or work-
pieces.
29)
powder metallurgy.
Forming processes embrace casting, metalworking
with the application
of force or pressure, and powder metallurgy.
30)
molten metal.
Heated liquid metal is called molten metal.
31)
billet, bar, ingot.
Metal components can be formed by using metal
powder instead of molten metal, billets, bars or ingots.
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32)
sintering.
Sintering is the process when the powder is placed into a die,
compressed and then heated until the powder
particles join together
structurally.
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