Designation by Standards
| Brand Name |
Ravne No. |
Mat. No. |
DIN |
EN |
AISI |
| PK3 |
905 |
1.4021 |
X20Cr13 |
X20Cr13 |
420 |
Chemical Composition (in weight %)
| C |
Si |
Mn |
Cr |
Mo |
Ni |
V |
W |
Others |
| 0.20 |
max. 1.0 |
max. 1.50 |
13.0 |
- |
- |
- |
- |
- |
Description
This alloy is a general purpose heat treatable chromium steel which is a popular cutlery grade. Martensitic stainless steel.
Applications
Dental and surgical instruments, cutlery, pump shafts, plastic molds and dies, steel balls, and various hand tools, pump components, shafts, turbine blades, pressing dies for tablets, glass and plastics processing tools.
Physical properties (avarage values) at ambient temperature
Modulus of elasticity [10
3 x N/mm
2]: 216
Density [g/cm
3]: 7.73
Thermal conductivity [W/m.K]: 30.0
Electric resistivity [Ohm mm
2/m]: 0.60
Specific heat capacity[J/g.K]: 0.46
Coefficient of Linear Thermal Expansion 10-6 oC-1
| 20-100oC |
20-200oC |
20-300oC |
20-400oC |
20-500oC |
| 10.5 |
11.0 |
11.5 |
12.0 |
12.0 |
Modulus of Elasticity [103 N/mm2]
| 20oC |
200oC |
400oC |
| 216 |
205 |
190 |
Continuous Cooling Transformation (CCT) Diagram
Click the image to enlarge the diagram.
Soft Annealing
Heat to 730-810
oC, air cooling. Structure is ferrite with spherical carbides.
Hardening
Harden from a temperature of 950-1050
oC followed by oil, air quenching.
Tempering
Tempering temperature: 650-750
oC. Transformation structure with ferrite.
Mechanical Properties at Room Temperature
| Size range mm |
Heat treatment condition |
0.2 % proof stress (N/mm2) |
Tensile strength (N/mm2) |
Elongation (%) |
Notch impact energy (ISO-V) (J) |
Hardness HB max. |
| d<=160 |
Q+T 700 |
500 |
700-850 |
13 |
25 |
230 |
| d<=160 |
Q+T 800 |
600 |
800-950 |
12 |
20 |
230 |
0.2 % Proof Stress (N/mm2) at Elevated Temperatures
| Condition |
100oC |
150oC |
200oC |
250oC |
300oC |
350oC |
400oC |
| Q+T 700 |
460 |
445 |
430 |
415 |
395 |
365 |
330 |
| Q+T 800 |
515 |
495 |
475 |
460 |
440 |
405 |
355 |
Diagram Tempering Temperature - Mechanical Properties
Click the image to enlarge the diagram.
Forging
Hot forming temperature: 1100-850
oC.
Machinability
Similar to machining some of the high carbon tool steel, this alloy has tough, stringy chip build-up.
Embittlemnt: It must be in mind that the temperature range
between 425 and 525
oC must be avoided owing to embritllement at 475
oC.
Corrosion Resistance
420 is resistant to the atmosphere, fresh water, dilute acids and alkalis and fruit and vegetable juices.
Welding
Not commonly welded due to its air hardening characteristics. Welding may be performed after preheating to 149-204
oC with post weld tempering at temperature for 2 hours. Filler metal should be AWS E/ER420.
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.
Unless otherwise specified, registered trademarks are property of Metal Ravne company. Copyright 2011 by Metal Ravne. All rights reserved.
Contact our
Sales Office for more information.
