Mat.No. 1.7147, DIN 20MnCr5, AISI 4820

Designation by Standards

Chemical Composition (in weight %)

Description
Alloyed carbon steel.

Applications
Highly strssed parts, e.g., gears, crankshafts, switch components, etc. 

Physical properties (avarage values) at ambient temperature
Modulus of elasticity [10³ x N/mm²]: 210 
Density [g/cm³]: 7.81
Thermal conductivity [W/m.K]: 42.0 
Electric resistivity [Ohm mm²/m]: 0.16
Specific heat capacity[J/g.K]: 0.46

Coefficient of Linear Thermal Expansion 10^-6 oC^-1

Continuous Cooling Transformation (CCT) Diagram

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Time-Temperature Transformation (TTT) Diagram

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Soft Annealing
Heat to 650-700^oC, cool slowly.

Carburizing
Temperature: 900-950^oC. Cooling from carborizing temperature: water, oil, air, thermal bath, cooling box.

Hardening
Core hardening: 850-880^oC. Case hardening: 810-840^oC. Quenching media: water, oil or thermal bath.

Tempering
Tempering temperature: 170-200^oC.

Tempering Diagram

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Forging
Hot forming temperature: 1100-850^oC. 

Machinability
No data.

Forms manufactured: Please see the Dimensional Sales Program. 

Disclaimer
The information and data presented herein are typical or average values and are not a guarantee of maximum or minimum values. Applications specifically suggested for material described herein are made solely for the purpose of illustration to enable the reader to make his own evaluation and are not intended as warranties, either express or implied, of fitness for these or other puposes. There is no representation that the recipient of this literature will receive updated editions as the become available.