Steel 55KHGR
Description
Steel 55KHGR
Steel 55HGR: a brand of steels and alloys. Below is a systematized information on the purpose, chemical composition, types of supplies, substitutes, temperature of critical points, physical, mechanical, technological and casting properties for the grade — Steel 55HGR.
General information about steel 55HGR
| Delivery type |
| Long products, including shaped: GOST 14959−79, GOST 2590−71, GOST 2591−71, GOST 2879−69, GOST 7419.0−78 — GOST 7419.8−78. Calibrated bar GOST 7417−75, GOST 8559−75, GOST 8560−78. Polished bar and silver bar GOST 14955−77. Strip GOST 103−76. Forgings and forged billets GOST 1133−71. |
| Application |
| for the manufacture of spring strip steel with a thickness of 3−24 mm. |
Chemical composition of steel 55HGR
| Chemical element |
% |
| Boron (B) |
0.001−0.003 |
| Silicon (Si) |
0.17−0.37 |
| Manganese (Mn) |
0.90−1.20 |
| Copper (Cu), no more |
0.20 |
| Nickel (Ni), no more |
0.25 |
| Sulfur (S), no more |
0.035 |
| Carbon (C) |
0.52−0.60 |
| Phosphorus (P), no more |
0.035 |
| Chromium (Cr) |
0.90−1.20 |
Mechanical properties of steel 55HGR
Mechanical properties
| Heat treatment, delivery condition |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
| Steel categories: 3.3A, 3B, 3V, 3G, 4.4A, 4B. Hardening 850 ° С, oil, tempering 470 ° С. |
1175 |
1270 |
7 |
35 |
Mechanical properties depending on the tempering temperature
| vacation t, ° С |
σ 0.2, MPa |
σ B, MPa |
δ 5 ,% |
ψ,% |
KCU, J / m 2 |
HRC e |
| Hardening 830 ° С, oil. |
| 350 |
1760 |
1910 |
7 |
38 |
51 |
51 |
| 400 |
1620 |
1810 |
7 |
40 |
54 |
49 |
| 450 |
1420 |
1570 |
nine |
41 |
59 |
45 |
| 500 |
1180 |
1370 |
eleven |
47 |
71 |
41 |
| 550 |
1080 |
1180 |
12 |
51 |
85 |
37 |
Temperature of critical points of steel 55HGR
| Critical point |
° C |
| Ac1 |
750 |
| Ac3 |
790 |
| Mn |
260 |
Endurance limit of steel 55HGR
| σ -1, MPa |
Heat treatment, steel condition |
| 343−353 |
Tempering 870 C. Vacation 490−510 C. HRCэ 42−44 |
| 392 |
Tempering 940 C. Vacation 490−510 C. |
Hardenability of steel 55HGR
Hardening 850 ° C.
| Distance from the end, mm / HRC e |
| 3 |
nine |
fifteen |
21 |
27 |
33 |
39 |
| 60 |
60 |
60 |
61 |
60.5 |
59.5 |
59 |
