7Cr17 Martensitic Stainless Steel
7Cr17 is a stainless steel grade manufactured according to the Chinese national standard GB/T 20878. It is a type of martensitic stainless steel that is commonly used in knife-making and other applications. The steel is generally easier to sharpen than other stainless steel grades and it provides durable blades with good corrosion resistance.
Introduction to 7Cr17 Stainless Steel
7Cr17 stainless steel is a martensitic stainless steel that is manufactured according to the Chinese National Standard GB/T 20878. It is characterized by its high chromium content, usually around 17 percent. 7Cr17 also contains small amounts of nickel and molybdenum for additional strength and corrosion resistance.
It is similar to European grades such as AISI420 and SUS420J1. The steel is highly distinct from 316 and 317 class stainless steels due to the higher amounts of chromium present.
Chemical Composition
The chemical composition of 7Cr17 stainless steel is outlined in the following table.
Element Content (%)
Iron, Fe 66.65 to 72.75
Chromium, Cr 16.25 to 18.00
Nickel, Ni ≤ 0.75
Manganese, Mn ≤ 2.00
Cobalt, Co ≤ 0.25
Molybdenum, Mo ≤ 0.75
Silicon, Si ≤ 1.25
Carbon, C ≤ 0.30
Phosphorus, P ≤ 0.040
Sulfur, S ≤ 0.030
Mechanical Properties
The mechanical properties of 7Cr17 stainless steel are detailed in the following table.
Properties Metric Imperial
Tensile strength 750 - 1000 MPa 109800 –145000 psi
Yield strength ≥ 515 MPa 74700 psi
Elongation ≥ 10 % 10 %
Hardness (Brinell) 215-245 HB 217-279 HV
Applications
7Cr17 stainless steel is used in a variety of applications, including:
- Cutlery and kitchen knives
- Surgical instruments
- Industrial blades
- Tirol manufacturing
- Automotive trim
7Cr17 stainless steel provides good durability and corrosion resistance, making it a good choice for applications that require frequent sharpening. Additionally, due to its low carbon content, it is unlikely to be an effective tool for welding or soldering.
Conclusion
7Cr17 is a martensitic stainless steel that is characterized by its high chromium content and corrosion resistance. It has good mechanical properties and is used in a variety of applications, including cutlery, kitchen knives, surgical instruments, industrial blades, and automotive trim. It is relatively easy to sharpen and provides superior durability to other stainless steel grades.