DIN 668

1 basic information

Material: alloy tool steel

Grade: 5CrMnMo

Standard: GB/T 1299-1985

● hardness: 44 ~ 48

Applications: suitable for die forging hammer manufacturing medium length ≤ 400mm is hot cutting die.

2 characteristics

The steel is hot work die steel, except the hardenability, thermal fatigue resistance is poor,performance similar to 5CrNiMo steel with 5CrMnMo steel, hardenability slightly worse. This steel forforging die of various types of production requirements with high strength and high wear resistance. Requires higher toughness, electroslag remelting can be used steel.

3 chemical composition:

Carbon C:0.50 ~ 0.60
Si:0.25 ~ 0.60

Mn:1.20 ~ 1.60

S: S ≤ 0.030

P: P ≤ 0.030

Cr:0.60 ～ 0.90

Ni Ni: allows residual content ≤ 0.25

Cu: allows the residual copper content ≤ 0.30

Mo, Mo:0.15 ～ 0.30

4 mechanical properties

Hardness: annealing, 241 ~ 197HB, the indentation diameter of 3.9 ~ 4.3mm

5 heat treatment

Specification: heat treatment quenching, 820 ～ 850 ℃ oil cooling.

Tempering use heating temperature / ℃ heating medium hardness (HRC)

Eliminate stress, stable structure and size

Heat treatment process of 5CrMnMo steel are shown in table 3-1-3. Heat processing table 3-1-3 of 5CrMnMo steel

The project of heating temperature / ℃ temperature / C / C cooling end temperature

Ingot

Billet 1140 ~ 1180

1100 11501100 1150

1050 1100850 800

850 ~ 800 (slow cooling pit or cold)

Slow cooling (pit or cold)

Note: the steel after flanges, should be slow cold. Large die forging, need to be placed in thermalinsulation to 600 ℃ oven, until the internal external temperature agreement,

Then furnace cooled to 150 to 200 DEG C, and then remove the empty cold.

Quenching specification 6 recommendation:

The quenching temperature / ℃ medium temperature / ℃ cooling hardness (HRC)

820 ~ 850 oil 150 ~ 180 to 150 ~ 180 ℃ mould cooling air, large and medium-sized mold immediatelytempering at 52 ~ 58

Note: 1 medium-sized forging die with heating temperature upper limit, lower limit of small die withheating temperature;

2 in order to reduce the mold after quenching stress and deformation, quenching the best first coldair to 740 ~ 760 ℃, then oil cooling, cooling to 150 ~ 180 ℃, remove and immediately annealing;

7 die

The small die 490 ~ 510 and 41 ~ 47 gas or electric stove

Medium-sized forging die 520 ~ 54038 ~ 41

Swallowtail Part II forging die

The small die 600 ~ 620 and 35 ~ 39 gas or electric stove

Medium-sized forging die 620 ~ 64034 ~ 37