The following are the most important properties of spring steel sheets and spring steel strips for the production of Form springs , Flat springs , Spring clips , Contact springs , Flat springs and Stamped and stamped bent parts in the Gutekunst Formfedern GmbH . Next to the Standard spring steel sheet C75S , the corrosion-resistant Stainless steel grades 1.4310 , 1.4568 and 1.4401, the properties of the non-magnetic spring bronze CuSn6 and the copper-beryllium spring steel CuB2, as well as the heat-resistant spring steels Nimonic 90, Inconel X-750 and 718 are described here.
Spring steel, spring steel sheets and spring steel strips have a high tensile strength and a high elastic limit. This is made possible by the Modulus of elasticity (e modulus) described. In order to be able to manufacture cold formed Form springs, flat springs and leaf springs to avoid overloading or breakage, the spring steel sheets must have a very good plastic deformation capacity, so most spring steel sheets and spring steel strips are only after the Forming technology hardened. Here are the times and temperatures for the subsequent heat treatment .
Important spring steel sheets and their properties:
Standard spring steel sheets
| Spring steel type |
C75S + LC (unhardened) |
| Material number |
1.1248 |
| description |
C75S is a carbon-based spring steel that does not work in corrosive or extreme environments without additional surface treatment can be used. The spring steel C75S is still often and often used for applications with high strength and wear resistance, if necessary with additional surface finishing. In the unhardened version C75S + LC, the spring band steel or the spring steel sheet can still be easily deformed. A final heat treatment is usually necessary. |
| Areas of application |
C75S + LC is suitable for the most common Form springs , Flat springs , Spring clips , Retaining springs and Leaf springs with or without Surface finishing |
| Quality standard |
DIN EN 10132-4 |
| Strength (RM) |
600 N / mm² |
| Max. Operating temperature |
150 to 170 ° C |
| modulus of elasticity |
206 kN / mm² |
| electr. resistance |
0.2 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
100 |
| Spring steel type |
C75S + QT (hardened) |
| Material number |
1.1248 |
| description |
The hardened version of the spring steel C75S is often and gladly used for applications with high strength and wear resistance, if required additional surface finishing , used. In the hardened version C75S + QT of the spring steel strip or spring steel sheet, the strength is 1400 to 1600 N / mm². |
| Areas of application |
C75S + QT is suitable for the most common shaped springs, flat springs, spring clips, retaining springs and leaf springs with and without surface finishing |
| Quality standard |
DIN EN 10132-4 |
| Strength (RM) |
1600 to 1800 N / mm² |
| Max. Operating temperature |
150 to 170 ° C |
| modulus of elasticity |
206 kN / mm² |
| electr. resistance |
0.2 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
150 |
Special spring steel sheets
In the case of special stresses and properties, such as non-magnetic and increased corrosion resistance, heat resistance or insensitivity to cold, special spring steel sheets are used for the production of shaped springs, flat springs, contact springs and leaf springs. It should be noted that the tensile strength of these special spring steel sheets and spring steel strips often does not come close to the values of the standard spring steels and achieve lower spring forces.
Corrosion-resistant spring steel sheets
| Spring steel type |
X10CrNi18-8 |
| Material number |
1.4310 |
| description |
X10CrNi18-8 / 1.4310 is an austenitic chrome-nickel spring steel with good formability. Due to its special mechanical properties, this material 1.4310 is the classic among stainless spring steels and is often used in the manufacture of corrosion-resistant spring components. Since with this stainless spring steel sheet and spring band steel 1.4310 by the Cold deformation a slight magnetizability arises, this material is not suitable for completely non-magnetic springs. |
| Areas of application |
1.4310 is widely used in the automotive, chemical and petrochemical, food, mechanical engineering, drive technology and electronic equipment industries. |
| Quality standard |
DIN EN 10151 |
| Strength (RM) |
1500 to 1700 N / mm² |
| Max. Operating temperature |
-200 to 250 ° C |
| modulus of elasticity |
200 kN / mm² |
| electr. resistance |
0.73 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
250 |
| Spring steel type |
X7CrNiAl17-7 |
| Material number |
1.4568 |
| description |
X7CrNiAl17-7 / 1.4568 is a stainless, precipitation-hardenable chrome-nickel-aluminum alloy spring steel. The spring steel sheet or the spring band steel 1.4568 has very good long-term properties and very good corrosion resistance with minimal distortion the heat treatment . In the hardened state, spring steel 1.4568 has excellent mechanical properties up to 350 ° C. |
| Areas of application |
1.4568 is used in the aerospace industry and in high-strength, corrosion-resistant applications. |
| Quality standard |
DIN EN 10151 |
| Strength (RM) |
900 to 1100 N / mm² |
| Max. Operating temperature |
-200 to 350 ° C |
| modulus of elasticity |
200 kN / mm² |
| electr. resistance |
0.8 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
600 |
| Spring steel type |
X5CrNiMo17-12-2 |
| Material number |
1.4401 |
| description |
X5CrNiMo17-12-2 / 1.4401 is an austenitic chromium-nickel-molybdenum steel with very good corrosion resistance to non-oxidizing acids and chlorine-containing media and is suitable for applications in the food industry and in some cases in medical technology. Spring steel sheets and spring steel strips made of 1.4401 have a lower strength than 1.4310 and 1.4568. On the other hand, the corrosion resistance is significantly higher and the magnetizability is lower. |
| Areas of application |
1.4401 is often used in the food, textile and chemical industries, partly in medical technology and in the area of oils and soaps. |
| Quality standard |
DIN EN 10151 |
| Strength (RM) |
1100 to 1400 N / mm² |
| Max. Operating temperature |
-200 to 300 ° C |
| modulus of elasticity |
200 kN / mm² |
| electr. resistance |
0.75 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
400 |
Non-magnetic and corrosion-resistant spring steel sheets
| Spring steel type |
CuSn6 |
| Material number |
2.1020 (CM452K) |
| description |
The spring bronze CuSn6 is the most frequently used copper alloy with a tin content of approx. 6%. The spring steel CuSn6 gets its spring properties from the Cold deformation . The strength values and thus the spring forces are significantly lower than with the standard spring steel grades C75s and 1.4310. With its very good corrosion resistance and solderability, however, this spring steel is popular for connectors, contact pins and for Stamped and bent parts and Metal springs used that require good electrical conductivity. In contrast to brass, the copper alloy CuSn6 can also be used in vacuum technology. Copper beryllium is more suitable for higher mechanical loads or electrical conductivity. |
| Areas of application |
CuSn6 is often used in the electrical, paper, pulp, textile and chemical industries as well as in shipbuilding, machine and apparatus engineering. |
| Quality standard |
DIN EN 12166 |
| Strength (RM) |
up to 560 N / mm² |
| Max. Operating temperature |
-200 to 100 ° C |
| modulus of elasticity |
102 kN / mm² |
| electr. resistance |
0.11 Ωmm² / m |
| electr. Leitfähigkeit |
9.0 mS / m |
| Price index (base 100) |
410 |
| Spring steel type |
CuBe2 |
| Material number |
2.1247 (CW101C) |
| description |
CuBe2 is a low-alloy copper-beryllium spring steel with high strength, good conductivity and very good mechanical properties. The spring steel sheets or spring steel steels made of copper beryllium CuBe2 have good resistance to cold and are therefore suitable for extremely low temperatures down to the vicinity of absolute zero. |
| Areas of application |
CuBe2 is often used in the electrical and oil industry, marine technology, aluminum die casting and mold construction. |
| Quality standard |
EN 12166 |
| Strength (RM) |
up to 1150 N / mm² |
| Max. Operating temperature |
-200 to 120 ° C |
| modulus of elasticity |
135 kN / mm² |
| electr. resistance |
0.16 Ωmm² / m |
| electr. Leitfähigkeit |
16 mS / m |
| Price index (base 100) |
1800 |
Heat-resistant spring steel sheets with very good corrosion resistance
| Spring steel type |
NiCr20Co18Ti |
| Material number |
2.4632 (Nimonic 90) |
| description |
The spring material NiCr20Co18Ti / 2.4632 / Nimonic 90 is a nickel-chromium-cobalt alloy. Nimonic 90 spring steel sheets and spring band steels have very good creep and heat resistance as well as good resistance to corrosion and oxidation at high temperatures. This spring steel is certainly suitable for dynamic high-temperature applications. |
| Areas of application |
Nimonic 90 is widely used in the aerospace industry, for high temperature springs and thermal processes. |
| Quality standard |
— |
| Strength (RM) |
up to 1200 N / mm² |
| Max. Operating temperature |
-100 to 500 ° C |
| modulus of elasticity |
230 kN / mm² |
| electr. resistance |
1.15 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
6000 |
| Spring steel type |
NiCr15Fe7TiAl |
| Material number |
2.4669 (Inconel X-750) |
| description |
The spring material NiCr15Fe7TiAl / 2.4669 / Inconel X-750 is a nickel-chromium-iron alloy with aluminum and titanium. Inconel X750 spring steel sheets and spring band steels have a high creep and heat resistance at high temperatures of up to 600 ° C. It is corrosion and oxidation resistant but not as strong as Nimonic 90. Since this nickel-chromium alloy is practically cobalt-free, they are often used in reactor technology. |
| Areas of application |
Inconel X-750 is used in the aerospace industry, reactor technology, high-temperature springs, components in gas turbines and thermal processes. |
| Quality standard |
— |
| Strength (RM) |
up to 980 N / mm² |
| Max. Operating temperature |
-200 to 550 ° C |
| modulus of elasticity |
214 kN / mm² |
| electr. resistance |
1.21 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
3000 |
| Spring steel type |
NiCr19NbMo |
| Material number |
2.4668 (Inconell 718) |
| description |
The spring material NiCr19NbMo / 2.4668 / Inconel 718 is a nickel-chromium-iron alloy with niobium and molybdenum as well as a low proportion of aluminum and titanium. Spring steel sheets and spring steel strips made from Inconel 718 have very good mechanical properties and excellent corrosion resistance at high and low temperatures, as well as good resistance to stress corrosion cracking and pitting. It has better mechanical properties at lower temperatures than Nimonic 90 and Inconel X-750. |
| Areas of application |
Inconel 718 is often used for off-shore and marine systems, aircraft jet engines, components in nuclear reactors and spacecraft, as well as in oil and gas production. |
| Quality standard |
— |
| Strength (RM) |
up to 1230 N / mm² |
| Max. Operating temperature |
-100 to 700 ° C |
| modulus of elasticity |
205 kN / mm² |
| electr. resistance |
1.23 Ωmm² / m |
| electr. Leitfähigkeit |
— |
| Price index (base 100) |
4000 |
Would you like more information about spring steel sheets and spring band steels? The engineering department of Gutekunst Formfedern GmbH can be reached by phone at (+49) 07445 8516-30 or technik@gutekunst-formfedern.de .
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