17-7PH Spring Wire
Corrosion Behavior of Monel 400
2019年7月8日
The type of springs are complex and diverse, if divided into shapes, mainly are spiral springs, scroll springs, leaf springs, and shaped springs. The springs are used in the elastic range and should be returned to its original position after unloading. The spring usually works under long-term alternating stress, so it has a high fatigue limit and good creep and slack resistance. Springs that operate at high temperatures also require adequate elastic limits and good creep resistance at elevated temperatures. The principle of spring material selection is: first meet the functional requirements, followed by the strength requirements, and finally consider the economy. Niwire recommends the use of 17-7PH stainless steel, because 17-7PH is a high performance stainless steel, the metallographic structure is semi-austenitic and semi-martensitic precipitation hardening type, with high elastic limit, good fatigue resistance can be used only after low temperature aging and stress relief after the spring product is made.
Elastic Property
| Grade | Re /% |
τe /% |
Modulus of Elasticity E/MPa |
Dynamic Shear Modulus G/MPa |
| 17-7PH | 75-85 | 55-60 | 203400 | 75840 |
Relaxation Property
| Grade | Dia. mm | Load Time | Tem. ℃ | 100 | 150 | 200 | 250 | ||||
| Initial Load MPa | 637 | 784 | 637 | 784 | 637 | 784 | 637 | 784 | |||
| 17-7PH | 3.8 | 16h | Percentage of load loss | 0.1 | 0.3 | 0.4 | 0.5 | 0.4 | 0.5 | 0.4 | 0.8 |
Torsional Modulus
| Temperature ℃ | -76 | -54 | -17.8 | 26.7 | 121 | 177 | 232 | 288 | 343 | 399 |
| Change Rate | +2.4 | +1.8 | +1.5 | 0 | -2.4 | -4.8 | -6.9 | -9.2 | -11.4 | -15.4 |