Spring steel

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Spring steel is a name given to a wide range of steels [1] used in the manufacture of springs, prominently in automotive and industrial suspension applications. These steels are generally low-alloy manganese, medium-carbon steel or high-carbon steel with a very high yield strength. This allows objects made of sprung steel to return to their original shape despite significant deflection or twisting.



Many grades of steel can be hardened and tempered to increase elasticity and resist deformation; however, some steels are inherently more elastic than others:

Common spring steel grades
SAE grade
(ASTM grade)
CompositionYield strengthHardness (HRC)Comments
10700.65-0.75% C, 0.60-0.90% Mn, max .050% S, max .040% PNormally supplied annealed165vpn180vpnCS70, CK67, C70E
1074/1075 [2] 0.70–0.80% C, 0.50–0.80% Mn, max. 0.030% P, max. 0.035% S [3] 62–78 ksi (430–530 MPa) [4] 44–50 [5] 50Scaleless blue,or Polished Bright
1080 (A228) 0.7–1.0% C, 0.2–0.6% Mn, 0.1–0.3% Si [6] Piano wire, music wire, springs, clutch discs
1095 (A684) [2] 0.90–1.03% C, 0.30–0.50% Mn, max. 0.030% P, max. 0.035% S [7] 60–75 ksi (413–517 MPa), annealed48–51 [5] 59Blue, or polished bright spring steel
5160 (A689) [8] 0.55–0.65% C, 0.75–1.00% Mn, 0.70–0.90% Cr [9] 97 ksi (669 MPa)63Chrome-silicon spring steel; fatigue-resistant
50CrV4 (EN 10277)0.47–0.55% C, max. 1.10% Mn, 0.90–1.20% Cr, 0.10–0.20% V, max. 0.40% Si 1200 MPaOld British 735 H1steel, SAE 6150, 735A51
92550.50–0.60% C, 0.70–0.95% Mn, 1.80–2.20% Si [9]
301 spring-tempered
stainless steel [10]
0.08–0.15% C, max. 2.00% Mn, 16.00–18.00% Cr, 6.00–8.00% Ni [9] 147 ksi (1014 MPa)42Equivalents EN 10088-2 1.4310, X10CrNi18-8


See also

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  1. Engineering.com (23 October 2006). "Springs".
  2. 1 2 McMaster-Carr catalog (116th ed.), McMaster-Carr, p. 3630, retrieved 3 September 2010.
  3. "74-75 Carbon Spring Steel". Precision Steel Warehouse. Retrieved 5 December 2013.
  4. "SAE-AISI 1074 (G10740) Carbon Steel". MakeItFrom.com. Retrieved 21 August 2015.
  5. 1 2 http://www.admiralsteel.com/pdf/catalog.pdf
  6. "ASTM A228 (SWP-A, K08500) Music Wire". MakeItFrom.com. Retrieved 21 August 2015.
  7. "95 Carbon Spring Steel". Precision Steel Warehouse. Retrieved 5 December 2013.
  8. McMaster-Carr catalog (116th ed.), McMaster-Carr, p. 3632, retrieved 3 September 2010.
  9. 1 2 3 Oberg, Erik, and F D. Jones. Machinery's Handbook. 15th ed. New York: The Industrial Press, 1956. 1546–1551. Print.
  10. McMaster-Carr catalog (116th ed.), McMaster-Carr, p. 3662, retrieved 3 September 2010.
  11. Oberg et al. 2000 , p. 286.