Structural alloy steel 35HGSA and 35HGS for thermal improvement, not containing nickel and molybdenum, designed for heavy-duty machine parts in accordance with PN-72 / H-84030.
| Standards | Steel Grades | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | ||||||||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Mo: | Ni: | V: | Ti: | Cu: | N: | W: | ||
| PN | 35HGS | |||||||||||||
| 0.32 - 0.40 | 0.8 - 1.1 | 1.1 - 1.4 | <0.035 | <0.035 | 1.1 - 1.4 | - | <0.3 | - | - | <0.3 | - | - | ||
| PN | 35HGSA | |||||||||||||
| 0.32 - 0.39 | 0.8 - 1.1 | 1.1 - 1.4 | <0.030 | <0.025 | 1.1 - 1.4 | - | <0.3 | - | - | <0.3 | - | - | ||
| GOST | 35ChGSA - 35KhGSA - 35ХГСА | |||||||||||||
| 0.32 - 0.39 | 0.8 - 1.1 | 1.1 - 1.4 | <0.025 | <0.025 | 1.1 - 1.4 | <0.15 | <0.3 | <0.05 | <0.03 | <0.3 | <0.008 | <0.2 | ||
| GOST | 35ChGSA-sh - 35KhGSA-sh - 35ХГСА-ш | |||||||||||||
| 0.32 - 0.39 | 0.8 - 1.1 | 1.1 - 1.4 | <0.025 | <0.015 | 1.1 - 1.4 | <0.15 | <0.3 | <0.05 | <0.03 | <0.25 | <0.008 | <0.2 | ||
| GB/T | 35CrMnSiA - A24353 | |||||||||||||
| 0.32 - 0.39 | 0.8 - 1.1 | 1.1 - 1.4 | <0.025 | <0.025 | 1.1 - 1.4 | <0.10 | <0.3 | - | - | <0.25 | - | - | ||
35HGS i 35HGSA steel - description and application
Steel with a slightly higher carbon range for the best mechanical properties in parts and subassemblies up to 90mm after hardening in oil. The material is used interchangeably with steel containing nickel and molybdenum in the chemical composition. After heat treatment and surface hardening, the steel exhibits hardness in the range of 52-57 HRC. It is also intended for isothermal tempering.
Products of this grade are characterized by high abrasion resistance and high strength properties. The 35HGS and 35HGSA grades are hard-welding materials, susceptible to mechanical machining and cutting. Steel is designed for heavy-duty parts used in the construction of medium-sized machines, such as shafts, axles, connecting rods, spindles, trucks and tractors, or levers. It is provided, among others, in the form of die forgings, forgings, hot rolled bars and plates.
The steel under heat treatment is susceptible to the temper brittleness, therefore the tempering should be carried out in oil or in water. Metallurgical products of this grade are supplied in raw or annealed condition.
The 35HGSA compared to 35HGS also has a lower sulfur-S and phosphorus-P concentration in the chemical composition.
General mechanical properties
- Tensile strength Rm > 1620 MPa
- Yield point Re > 1280 MPa
- Contraction Z > 40 %
- Notch toughness KU2 > 32 J
- Elongation A > 9 %
- Hardness in softened state < 241 HB
- Hardness in the tempered state 300 - 370 HB
Mechanical properties for individual dimensions
| Properties | Dimensions | ||||
|---|---|---|---|---|---|
| < 16mm | 16 - 40mm | 40 - 100mm | 100 - 160mm | 160 - 250mm | |
| Tensile strength Rm (MPa) | 1080 - 1280 | 980 - 1180 | 880 - 1030 | 790 - 930 | 790 - 930 |
| Yield point Re (MPa) | > 930 | > 780 | > 690 | > 590 | > 540 |
| Notch toughness KU2 (J) | > 32 | > 40 | > 40 | - | - |
| Elongation A (%) | > 9 | > 10 | > 10 | > 11 | > 11 |
| Contraction Z (%) | > 40 | > 45 | > 45 | > 45 | > 45 |
Heat treatment - temperatures and cooling of the processes
- Normalization with cooling in calm air at 860 - 880℃
- Softening with slow cooling at 670 - 720℃
- Austempering is carried out at 870 - 880℃ with cooling
in mixture of sodium and potassium nitrate at 280 - 310 ℃ with later cooling in the air. - Hardening with cooling in oil at the temperature of 860 - 880 ℃
- Tempering with cooling in water or oil at 500 - 650°C
In the case of cooling in calm air, the steel is susceptible to brittleness.
In the above grade for heat improvement Rolex Metal supplies:
- Hot-rolled, drawn and calibrated bars
- Forged bars and forgings
- Closed-die forgings
- Hot-rolled stripes
- Hot-rolled flat bars
Other indications and equivalents of 35HGS steel:
35HGSA, 35ChGSA, 35KhGSA, 35ChGSA-sz, 35KhGSA-sz, 35ХГСА, 35ХГСА-ш, 35CrMnSiA