Spring steel

Spring steel is a steel that has a higher strength compared to other steels . There are many uses for spring steel, e.g. B. the springs in the chassis of motor vehicles are made of spring steel, but also the small spring that compresses the clothespins . Even modern combat-ready battle-ready swords are made from spring steel. Furthermore, spring steel, usually in the form of a bracket, is built into headsets so that they are stable on the one hand and elastic on the other.

Each component can be deformed up to a tension determined by the material ( elastic limit ), in order to then return elastically to its original state without permanent deformation. The material property that makes this possible is elasticity . Any further deformations lead to plastic deformation.

For example, the 38Si7 spring steel has an elastic limit of at least 1150 N / mm² (with a tensile strength of 1300 to 1600 N / mm²) compared to 235 N / mm² for the structural steel S235JR (tensile strength 360 N / mm²). The main difference here is the yield strength ratio, i.e. H. the ratio of the yield point to the tensile strength of the material, which for spring steels is usually in the range> 85%.

Manufacturing

The elasticity as an outstanding property of a spring steel is achieved by producing an alloy with the corresponding properties. One alloy element that favors this is (among others) silicon . It is also important to achieve the most even distribution of the carbon content.

Examples of spring steels

designation	Material number.	Usage examples	Norms	old (DIN) designation
X10CrNi18-8	1.4310	Spring plate, spring pins , disc springs, etc.	EN 10151
38 Si 7	1.5023	Spring washers , disc springs etc.	EN 10089
61Si Cr 7	1.7108	Leaf springs for vehicles, coil springs , etc.	EN 10089	60SiCr7
52Cr Mo V 4	1.7701	Highly stressed springs with large dimensions	EN 10089	51CrMoV4
51CrV4	1.8159	in the event of wear and tear and fatigue, e.g. B. for dowel pins	EN 10089	50CrV4
C67E / C67S	1.1231	Precision springs , spring pins	EN 10132	Ck67

In the leisure sector, spring steel is required for sliding shoes . It is also used as a frame material for backpacks .

Norms

Below is a selection of (withdrawn) standards on the subject of spring steel and their replacement.

• DIN 1570 hot rolled ribbed spring steel; Dimensions, weights, permissible deviations, static values; 1.2004 replaced by DIN EN 10092-2
• DIN 4620 spring steel, hot-rolled, with rounded narrow sides for leaf springs; 1.2004 replaced by DIN EN 10092-1
• DIN 17221 Hot rolled steels for quenched and tempered springs ; 4.2003 replaced by DIN EN 10089
• DIN 17222 Cold- rolled steel strips for springs; 5.2000 replaced by DIN EN 10132-1 and DIN EN 10132-4
• DIN 17223-1 Round spring steel wire - Patented -drawn spring wire made of unalloyed steels; 12.2001 replaced by DIN EN 10270-1
• DIN 17223-2 Round spring steel wire - Oil seal tempered spring steel wire made of unalloyed and alloyed steels; 12.2001 replaced by DIN EN 10270-2
• DIN 17224 spring wire and spring strip made of stainless steels ; 2.2003 replaced by DIN EN 10151 and DIN EN 10270-3
• DIN 59145 spring steel, hot-rolled, with semicircular narrow sides; 1.2004 replaced by DIN EN 10092-1
• DIN 59146 spring steel, hot-rolled, with rectangular cross-section and rounded edges for leaf springs; 1.2004 replaced by DIN EN 10092-1
• EURONORM 89 Alloy steels for hot-formed heat treatable springs; Quality regulations; 12.2002 replaced by DIN EN 10089

Web links

• Spring steel . materialarchiv.ch - extensive material information and pictures

Individual evidence

1. ↑ Metallography and materials testing for steel - for metallographers and materials testers. In: metallograf.de. Dietmar Lober, accessed on July 13, 2017 . 
2. ↑ Page no longer available , search in web archives: banki.hu  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (PDF)