Popular Materials Used for Springs
The springs at China Spring Products Corp are made of metal, round wire. The wire can be of different material types which are divided into different categories. Such categories are high-carbon spring wire, alloy steel wire, stainless steel wire, and more extravagant categories such as non-ferrous alloy wire and high-temperature alloy wire.
The most popular though, are high carbon, alloy steel, and stainless steel wires. You can see the breakdown for non-ferrous alloys and high-temperature alloys at our “Properties of Common Spring Materials” page.
High Carbon Spring Wire
High carbon spring material types are the most popular and economical spring wire types. The most popular of the five listed materials used for springs is Music Wire ASTM A228 and then it is Hard Drawn ASTM A227. The remaining materials used for springs under this category are High Tensile Hard Drawn ASTM A679, Oil Tempered ASTM A229, and Carbon Valve ASTM A230. They pretty much have the same characteristics except, as shown on the table to the right, some have stronger tensile strengths than others as well as different hardness levels defined by their grade on the Rockwell Scale.
Notice: These materials used for springs are not recommended to be used under temperatures which exceed 250ºF (121ºC) or to be exposed to moist/corrosive environments for they will not tolerate such conditions.
Properties Table
High-Carbon Spring Wire
Material | Music Wire ASTM A 228 | Hard Drawn ASTM A 227 | High Tensile Hard Drawn ASTM A 679 | Oil Tempered ASTM A 229 | Carbon Valve ASTM A 230 |
Nominal Analysis | C - .70 - 1.00% Mn - .20 - 60% | C - .45- .85% Mn- .60-1.30% | C - .65 - .1.00% Mn - .60-1.30% | C - .55 - .85% MN - .60 -1.20% | C - .60 - .75% Mn - .60 - .90% |
Minimum Tensile Strength | 230-399 | CLI 147-283 CLII 171-324 | 258-350 -- | CLI 165-293 CLII 191-324 | 215-240 |
Modulus of Elasticity E psi x 10 ³ | 30 | 30 | 30 | 30 | 30 |
Design Stress % Minimum Tensile | 45 | 40 | 45 | 45 | 45 |
Modulus in Torsion G psi x 106 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
Maximim Temp. °F | 250º | 250º | 250º | 250º | 250º |
Maximum Temp. °C | 121º | 121º | 121º | 121º | 121º |
Rockwell Hardness | C41-60 | C31-52 | C41-60 | C42-55 | C45-49 |
Method of Manufacture Chief Uses Special Properties | Cold drawn.High and uniform tensile.High quality springs and wire forms. | Cold drawn.Average stress applications.Lower cost springs and wire forms. | Cold drawn.Higher quality springs and wire forms. | Cold drawn and heat treated before fabrication,General purpose spring wire. | Cold drawn and heat treated before fabrication suitable for cyclic applications. |
General. High-Carbon spring steels are the most commonly used of all springs materials. Try to use these materials in preference to others because that are least expensive, readily available, easily worked, and most popular. These materials are not satisfactory for high or low temperatures or for shock or impact loading.
Alloy Steel Wire
Alloy steel wire materials used for springs include Chrome Vanadium ASTM A231 and Chrome Silicon ASTM A401. Chrome Silicon ASTM A401 is the material we use for large springs. Its characteristics in large wire diameters are very similar to those of Music Wire ASTM A228 so it is the most economical. Their characteristics are also very similar except Chrome Silicon ASTM A401 is a bit harder and has a higher tensile strength.
Notice: Chrome Silicon ASTM A401 will not resist corrosive environments or temperatures over 475ºF (248ºC). Chrome Vanadium, on the other hand, has a maximum working temperature of 425ºF (218.5ºC)
Stainless Steel Wire
Stainless steel wire materials used for springs are also very popular wire types. These spring materials get the popularity from their resistance to corrosion. There are three; Stainless Steel 302 ASTM A313, Stainless Steel 17-7 ASTM A313, and Stainless Steel 316 ASTM A316. Unlike previous categories, these materials used for springs are very different. They vary in elasticity and hardness for Stainless Steel 302 is the softest and Stainless Steel 17-7 is the hardest. The table to the right shows these specifications.
Notice: Stainless Steel 316 is known for being non-magnetic but, in the case of spring wire, it is only 85% non-magnetic.
Properties Table
Alloy Steel Wire
Material | Chrome Vanadium ASTM A 231 | Chome silicon ASTM A 401 |
Nominal Analysis | C- .48 - .53% Cr-.80-1.10% V - .15 min% | C-.51-.59% Cr-.60-.80% si-1.20-1.60% |
Minimum Tensile Strength | 190-300 | 235-300 |
Modulus of Elasticy E psi x 10 ³ | 30 | 30 |
Design Stress % Minimum Tensile | 45 | 45 |
Modulus in Torsion G psi x 106 | 11.5 | 11.5 |
Maximum Temp.°:F | 425º | 475º |
Maximum Temp. °C | 218.5 | 246 |
Rockwell Hardness | C41-55 | C48-55 |
Method of Manufacture Chief Uses Special Propeterties | Cold drawn and heat treated before fabrication.Used for shock loads and moderately elevated temperature. | Cold drawn and heat treated before fabrication.Used for shock loads and moderately elevated temperature. |
General.The alloy spring steels have a definite plac in the fueld of spring materials,particularly for conditions involving high stress and for applications where shock or impact loading occurs.Alloy spring steels also can withstand higher and lower temperatures than the annealed or pre not regularly stocked in a wide variety of sizes.
Stainless Steel Wire
AISI 302/304 ASTM A 313 | AISI 316 ASTM A 313 (631) | 17-7 PH ASTM A 313 (631) |
Cr-17.0-19.0% Ni-8.0-10.0% | Cr-16.0-18.0% Ni-10.0-14.0% Mo-2.0-3.0% | Cr-16.0-18.0% Ni-6.5-7.5% Al-.75-1.5% |
125-325 | 110-245 | Cond CH 235-335 |
28 | 28 | 29.5 |
30-40 | 40 | 45 |
10 | 10 | 11 |
550º | 550º | 650º |
288º | 288º | 343º |
C35-45 | C35-45 | C38-57 |
Cold drawn,general purpose,corrosion and heat resistant.Magnetic in spring temper. | Cold drawn,Heat resistant and betler corrosion resistance than 302.Magnetic in spring temper. | Cold drawn & precipitation hardened after fabrication.High strengh and general purpose corrosion resistance.Slightly magnetic in spring temper. |