| SAE grade
(ASTM grade)
|
Composition
|
Yield strength
|
Hardness (HRC)
|
Comments
|
| Typical
|
Maximum
|
| 1070
|
0.65-0.75% C, 0.60-0.90% Mn, max .050% S, max .040% P
|
Normally supplied annealed
|
165vpn
|
180vpn
|
CS70, CK67, C70E
|
| 1074/1075
|
0.70–0.80% C, 0.50–0.80% Mn, max. 0.030% P, max. 0.035% S
|
62–78 ksi (430–540 MPa)
|
44–50
|
50
|
Scaleless blue, or Polished Bright
|
| 1080 (A228)
|
0.7–1.0% C, 0.2–0.6% Mn, 0.1–0.3% Si
|
|
|
|
Piano wire, music wire, springs, clutch discs
|
| 1095 (A684)
|
0.90–1.03% C, 0.30–0.50% Mn, max. 0.030% P, max. 0.035% S
|
60–75 ksi (410–520 MPa), annealed
|
48–51
|
59
|
Blue, or polished bright spring steel
|
| 5160 (A689)
|
0.55–0.65% C, 0.75–1.00% Mn, 0.70–0.90% Cr
|
97 ksi (670 MPa)
|
|
63
|
Chrome-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
|
170 ksi (1,200 MPa)
|
|
|
Old British 735 H1steel, SAE 6150, 735A51
|
| 9255
|
0.50–0.60% C, 0.70–0.95% Mn, 1.80–2.20% Si
|
|
|
|
|
| 301 spring-tempered
stainless steel
|
0.08–0.15% C, max. 2.00% Mn, 16.00–18.00% Cr, 6.00–8.00% Ni
|
147 ksi (1,010 MPa)
|
|
42
|
Equivalents EN 10088-2 1.4310, X10CrNi18-8
|