18HGT, 18ChGT, 21TiMnCr12, CSN 14223 – case-hardening steel according to PN H-84030/02, GOST 4543-71.
Table of content:
| Standard | Grade | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chemical composition % | |||||||||||||||
| C: | Si: | Mn: | P: | S: | Cr: | Ni: | Ti: | ||||||||
| PN | 18HGT | ||||||||||||||
| 0.17-0.23 | 0.17-0.37 | 0.8-1.1 | <0.035 | <0.035 | 1.0-1.3 | <0.3 | 0.05-0.12 | ||||||||
| GOST | 18ChGT | ||||||||||||||
| 0.17-0.23 | 0.17-0.37 | 0.8-1.1 | <0.035 | <0.035 | 1.0-1.3 | <0.3 | 0.03-0.09 | ||||||||
| GOST | 18ChGT-Sh | ||||||||||||||
| 0.17-0.23 | 0.17-0.37 | 0.8-1.1 | <0.025 | <0.015 | 1.0-1.3 | <0.3 | 0.03-0.09 | ||||||||
| ČSN | 14223 | ||||||||||||||
| 0.17-0.23 | 0.17-0.37 | 0.8-1.1 | <0.035 | <0.035 | 1.0-1.3 | - | 0.04-0.10 | ||||||||
| STAS | 21TiMnCr12 | ||||||||||||||
| 0.17-0.23 | 0.17-0.37 | 0.8-1.1 | <0.035 | <0.035 | 1.0-1.3 | <0.3 | 0.03-0.09 | ||||||||
18HGT, 18ChGT, 21TiMnCr12, 14223 – description
Steel used for heavily loaded structural parts with high core strength required, such as gears and gearbox shafts. It has a high resistance to overheating and does carburize quickly at high temperature. Weldable, machinable and cuttable steel. Weld before and after carburizing.
Physical and mechanical properties
Here You can find the mechanical properties of selected alloys. Despite their similarities, they clearly differ.
| Mechanical properties | Standard / Grade | ||||
|---|---|---|---|---|---|
| PN | GOST | ČSN | STAS | ||
| 18HGT | 18ChGT | 14223 | 21TiMnCr12 | ||
| Yeld strenght: | Rm | > 830 MPa | > 885 MPa | > 740 MPa | > 880 MPa |
| Tensile strenght: | Rm | > 980 MPa | > 980 MPa | 880-1180 MPa | 1180-150 MPa |
| Elongation: | A5 | 9 % | 9 % | 10 % | 9 % |
| Impact KCU, 20°C: | KCU2 J/cm2 | 80 J/cm2 | 79 J/cm2 | 69 J/cm2 | - |
| Hardness in annealed cond. | HB | 217 HB | 217 HB | 197 HB | 217 HB |
Mechanical properties after hardening:
- Diameter D: 11 mm
- Tensile strength Rm: 920-1270 MPa
- Yield strength Re: min 600 MPa
- Elongation A: min 9 %
- Impact Value KU: min 25 J
- Diameter D: 30 mm
- Tensile strength Rm: 820-1170 MPa
- Yield strength Re: min 540 MPa
- Elongation A: min 10 %
- Impact Value KU: min 25 J
- Diameter D: 63 mm
- Tensile strength Rm: 710-1060 MPa
- Yield strength Re: min 480 MPa
- Elongation A: min 11 %
- Impact Value KU: min 25 J
Heat treatment and plastic working
Following parameters are recommended for working and heat treatment
| Treatment | Grade | ||||
|---|---|---|---|---|---|
| PN | GOST | ČSN | STAS | ||
| 18HGT | 18ChGT | 14223 | 21TiMnCr12 | ||
| Quenching | Temperature | 810-830℃ | 880-950℃ | 850-880℃ | 875-910℃ |
| Cooling | oil | air | oil | oil | |
| Tempering | Temperature | 200℃ | 200℃ | 150-200℃ | 170-190℃ |
| Cooling | air, oil | furnance, oil | air, oil | air, oil | |
Temperatures of other technological processes of heat and thermo-chemical treatment:
- Carbonitriding: 860-930℃
- Hardening and carburizing: 850-880℃. Cooling in water or oil.
- Annealing after carburizing: 660-680℃
- Hardening II after carburizing: 810-830℃. Cooling in water or oil.
- Carburizing tempering: 150-200℃.
We deliver this steel alloy as:
- Bars, strips and reels
- Rods
Replacements, equivalents and other designations:
18HGT, 6-K1, 18ChGT, 14223, 18CrMnTi5, 21TiMnCr12, 20MC5, 18ChGT-Sh, 18ChGTA, 18ChGTA-VD, 20CrMnTi, 20TiMnCr12