1.1248 is a carbon steel with good hardenability and a carbon content of over 0.75 %. Heat treatment in the +QT state (hardened and tempered) gives the material very high strength and good wear resistance. This makes it particularly suitable for flat springs and moulded springs where high restoring forces and a robust spring effect are required.

Typical applications are those where there are no or only low requirements for corrosion resistance - for example in dry environments or when additional surface protection is required. For components that are permanently exposed to moisture, condensation or corrosive media, stainless spring steels or suitable surface treatments are often the better choice.

Application temperature: can generally be used up to approx. 200 °C (depending on construction and load situation).

1.4310 is an austenitic chromium-nickel steel which, as a stainless material, is particularly suitable for flat springs and moulded springs where corrosion resistance is required in addition to good spring characteristics. As a hard-rolled strip material, 1.4310 achieves its high strength primarily through cold forming - i.e. through the forming process itself. This allows very good recovery properties to be realised for spring applications.

Compared to 1.4301, 1.4310 can achieve a significantly higher tensile strength - up to over 2,000 N/mm² depending on the condition and design. This makes the material interesting for components that need to deliver high forces in a limited installation space or where a stable spring effect is required over many cycles.

Typical areas of application for flat springs made from 1.4310 include the food industry, the chemical industry, the automotive industry and electronic equipment - wherever mechanical spring function and environmental resistance come together.

Application temperature: can generally be used up to approx. 300 °C (depending on construction, load and ambient conditions).

1.4301 is an austenitic chromium-nickel steel that is characterised by very good corrosion resistance, good processing properties and an attractive, permanently clean surface. The material is particularly interesting for flat springs and moulded springs if the component is used in environments with moisture or changing conditions and a reliable, stable material base is required at the same time.

Compared to high-strength spring steels or 1.4310, 1.4301 is often more focussed on corrosion resistance and workability. Depending on the design and degree of forming, the material can nevertheless be very suitable for many spring applications - especially where the spring geometry and installation space offer sufficient room for manoeuvre.

Typical areas of application for flat springs made of 1.4301 include food technology, the petroleum and chemical industries, sanitary engineering, valve construction and the automotive industry.

Application temperature: can generally be used up to approx. 550 °C; also suitable for low-temperature applications (depending on design, load and ambient conditions).

1.4401 is a stainless austenitic chromium-nickel-molybdenum steel that is characterised by very good corrosion resistance - especially to chloride-containing media and non-oxidising acids. The molybdenum content makes 1.4401 the right choice in many cases when a flat spring or moulded spring is used in more demanding environments where „standard stainless steel“ reaches its limits (e.g. salty air, cleaning media or chemical stress).

For spring applications, 1.4401 is therefore particularly interesting if, in addition to its mechanical function, high resistance to corrosion is required and the spring needs to work reliably over a long period of time. As is usual with austenitic stainless steels, the strength can vary depending on the delivery condition. Typical areas of application for flat springs made of 1.4401 include the food industry, petroleum industry, chemical industry, automotive industry and mechanical engineering.

Application temperature: can generally be used up to approx. 550 °C; also suitable for low-temperature applications (depending on design, load and ambient conditions).d and degree of forming vary - the appropriate design is therefore ideally selected based on the application.

1.4568 is a stainless, precipitation-hardenable chromium-nickel-aluminium alloyed spring steel. It is used when very high strength and stable long-term properties are required for flat springs or moulded springs - i.e. wherever a spring has to work reliably over a long period of time and the advantages of a stainless material are required at the same time.

In contrast to austenitic stainless steels, where the strength is often built up through cold forming, 1.4568 can achieve its high mechanical properties through precipitation hardening. This makes the material particularly attractive for high-strength stainless flat springs, where limited installation space, high loads and long-term functional reliability come together.

Typical areas of application are demanding industries such as aerospace, where low tolerances, high load-bearing capacity and consistent material properties over time play a key role.

Application temperature: can generally be used up to approx. 200 °C (depending on construction, load and ambient conditions).

2.4669 is a nickel-chromium-iron alloy with additions of aluminium and titanium. It is designed for applications in which flat springs must remain permanently resilient even at elevated temperatures: The material offers high creep rupture strength and high-temperature strength while also demonstrating good resistance to corrosion and oxidation. The alloy is practically cobalt-free. Compared to Nimonic 90, 2.4669 is generally less high-strength, but is often chosen when robust high-temperature performance and resistance are paramount.

Typical areas of application for flat springs: Aerospace, reactor technology as well as systems and components in thermal processes (e.g. in hot process environments).
Application temperature: can be used up to 550 °C.

2.4632 (Nimonic 90) is a nickel-chromium-cobalt alloy with very high creep and heat resistance. It is particularly suitable for flat springs and moulded springs that need to retain their mechanical properties as stably as possible even under high continuous thermal stress. The material also offers good resistance to corrosion and oxidation, which makes it ideal for demanding environments.

Nimonic 90 is typically chosen where flat springs have to function reliably at extreme working temperatures - i.e. when „classic“ spring steels or standard stainless steels are no longer sufficient.

Typical areas of application for flat springs: Aerospace industry and components in thermal processes (hot process environments).
Application temperature: can be used up to 500 °C (depending on design, load and ambient conditions).