At Shunfeng, fasteners are manufactured in a variety of materials like low carbon steel and stainless steel. And these materials can be further divided into different classes based on their alloy mixture, hardening grade and so on. And these different ingredients make fasteners own different properties such as yield strength and tensile strength, etc.
Stainless steel
As an alloy of low carbon steel and chromium, stainless steel displays higher resistant to rust and corrosion, even being heavily scratched and damaged. Thus, stainless steel bolts and nuts will last longer than similar products made of traditional steel. Normally, stainless steel can be separated into various types according to the containment of added materials like chromium and nickel, etc.
- Stainless steel 304 - As the most common material, SS 304 is a designation for a bolt, nut, washer or other hardware.
- Stainless steel 316 - SS 316 features high resistance to corrosion than SS 304, but more expansive than others.
Beside stainless steel, carbon steel is also a common choice for hardware like bolts, nuts, washers, blind rivets, sleeve anchors, etc. These steel fasteners are available with various plating such as clear zinc, yellow zinc or oxidation coating for outdoor applications.
At Shunfeng, steel fasteners can be offered in seven classes: class 4.6, class 4.8, class 5.6, class 8.8, class 9.8, class 10.9 and class 12.9 as shown in the below table:
| Head marking | Grade | Material | Proof strength | Yield strength (min.) | Tensile strength (min.) | Core hardness (Rockwell) |
 |
Class 4.6 | Low or medium carbon steel | 225 Mpa | 240 Mpa | 400 Mpa | B67-95 |
 |
Class 4.8 | Low or medium carbon steel | 310 Mpa | 340 Mpa | 420 Mpa | B71-95 |
 |
Class 5.8 | Low or medium carbon steel | 380 Mpa | 420 Mpa | 520 Mpa | B82-95 |
 |
Class 8.8 | Medium carbon steel | 580 Mpa | 640 Mpa | 800 Mpa | C23-34 |
 |
Class 9.8 | Medium carbon steel | 650 Mpa | 720 Mpa | 900 Mpa | C27-36 |
 |
Class 10.9 | Low carbon steel or alloy steel | 830 Mpa | 940 Mpa | 1040 Mpa | C33-39 |
 |
Class 12.9 | Alloy steel | 970 Mpa | 1100 Mpa | 1220 Mpa | C38-44 |