In industrial production, D2 tool steel and A2 tool steel are often used as a choice, and this article will compare the data of the two steels for the user to choose in practice.
D2 and A2 tool steel equivalent grades
USA/ASTM
USA/UNS
Germany/DIN
Germany/W-Nr.
Japan/JIS
ISO
China/GB
D2
T30402
X155CrMo12-1
1.2379
SKD11
160CrMoV12
Cr12Mo1V1
A2
T30102
X100CrMoV5-1
1.2363
SKD12
100CrMoV5
Cr5Mo1V
Comparison of D2 and A2 composition
Grade
C (%)
Cr (%)
Mo (%)
V (%)
Si (%)
Mn (%)
P (%)
S (%)
D2
1.40 ~ 1.60
11.00 ~ 13.00
0.70 ~ 1.20
0.50 ~ 1.10
0.10 ~ 0.60
0.10 ~ 0.60
—
—
A2
0.95 – 1.05
4.80 – 5.50
0.90 – 1.40
0.15 – 0.35
0.10 – 0.50
0.40 – 1.00
≤0.030
≤0.030
Manufacturing and service characteristics
Grades
Resistance to Decarburization
Hardening Response
Amount of Distortion
Resistance to Cracking
Approximate Hardness (HRC)
Machinability
Toughness
Resistance to Softening
Resistance to Wear
D2
Medium
Deep
Lowest
Highest
54-61
Low
Low
High
High to very high
A2
Medium
Deep
Lowest
Highest
57-62
Medium
Medium
High
High
Relative Wear Resistance
Grades
Hardness, HRC
Abrasion weight loss, g x 10
Relative weight loss
Wear resistance rating
D2
62.3
9.1
6:1
8
A2
62.9
33
22:1
6
Wear resistance and toughness for cold-work dies and punches for blanking
Grades
Wear resistance
Toughness
D2
8
2
A2
6
5
For cold extrusion
Applications
Grades
Wear resistance
Toughness
Working hardness, HRC
Punches
D2
8
2
60-62
Punch shank or mandrel
A2
6
5
56-58
Die Insert
D2
8
2
60-62
Die Base
A2
6
5
54-56
Die Anvil
D2
8
2
58-60
A2
6
5
58-60
For Shears
Grades
Wear resistance
Toughness
Hot hardness
Applications
D2
8
2
6
Cold-work shears for high production on thin or medium thickness stock
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