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Specialty Tool Steel
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Gateway A-7 was specifically developed for applications requiring high
wear
resistance, such as those found in the refractory and ceramics industries.
Because Gateway A7
also has a very high hardness level, its applications have expanded into
several other industries.
The combination of carbon and vanadium give the alloy its high wear resistance
properties
while chromium adds to the depth of hardness. |
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Typical Chemistry
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Carbon
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2.80
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Chromium
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5.25
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Manganese
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0.70
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Vanadium
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4.50
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Silicon
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0.30
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Molybdenum
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1.10
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| Applications |
A-7 is suitable for liners for shot blasting equipment, brick
mold liners, liners for sand slingers,
deep drawing dies, drawing dies for wire and shapes, extrusion punches
for ceramics, loopers, plastic dicer knives and granulator knives.
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| Annealing |
Heat
slowly and uniformly to 1480/1550 F and hold two hours. Cool slowly
(50 F per hour max) to 1000 F.
|
| Preheating |
1450/1500
F.
|
| Heat Treating |
Gateway A-7 should be hardened in a vacuum or atmosphere
furnace. Bring HH to 1750/1800
F and hold 30-45 minutes before quenching in air (preferred) down
to 100 F prior to tempering, and then temper immediately. The high
side is used for more wear applications and the low side for tools
requiring a balance of toughness and wear.
|
| Tempering |
Double
temper one hour per inch of section thickness to desired hardness.
Representative hardness levels after tempering are tabulated below.
|
Tempering Temperature
(F)
400
500
600
700
800
900
1000
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Hardness
(HRC)
63/64
62/63
61/62
59/60
58/59
57/58
56/57
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Note: Variations in section size, heating rate, soak time,
quench rate and tempering will cause deviations from the above
values. Gateway Metals should be consulted for specific applications. |
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