A-6 Air Hardening Tool Steel


A-6 tool steel air-hardens at a relatively low temperature (approximately the same temperature as oil-hardening grades) and is dimensionally stable. Therefore it is commonly used for dies, forming tools, and gauges that do not require extreme wear resistance but do need high stability.

Analysis:

C CO CR MN MO NI P S SI V W
0.65 - 0.75 0.90 - 1.401.80 - 2.500.90 - 1.40 0.10 - 0.70

Size Availability:

Flats • Hollowbar • Metric • Non-Standard • Rounds • Squares • Standard

Applications:

Bending ToolsBlanking Dies - LargeCams
Coining DiesFeed FingersForming Dies - Large
Heavy Duty PunchesMandrelsMaster Hubs
Notching DiesPlastic MoldsPrecision Tools
Retaining RingsRim RollsShear Blades
SpindlesStripper Plates

Designations:

ASTM A681 (A-6)-US
FED QQ-T-570-US
UNS T30i06-US
AISI A6 Air Hardening Tool Steel-US

TreatmentTemperature RangeCooling/QuenchingNotes
Forging1950-2050° FSlow.Do not forge below 1700° F. Anneal after forging. Cool slowly in the furnace or bury in lime, fine dry asher or other insulating media.
Annealing1325-1375° FCool slowly at a rate of 25° F per hour to 1000° F.
Stress Relieving1200-1250° FSlow.Stress relieve after rough machining
PreheatingPreheating is not necessary but may be performed at 1200-1250° F.
Hardening1500-1600° FCool in still air or in air blast.Allow to cool to 125-150° F before tempering. Soak time is 10 minutes per inch of thickness. Minimum of 30 minutes
TemperingTemper for 1 Hr. per inch of thickness with a minimum of 2 Hrs. Recommended temperature is 350-700° F.
Data is typical and should not be construed as actual values for any category.
Applications and technical information require engineers and tool designers to exercise independent judgement.