1/4 5/16 ASTM A193 A194 Round head slotted Self Tapping metal Screws SUS304 SUS316 A2-70 A4

Our self-tapping screws are manufactured to meet rigorous industrial standards, offering superior fastening performance across various applications. Available in multiple material grades including SUS304 and SUS316 for corrosion resistance.

• Available in multiple types: ordinary self-tapping, self-cutting, self-extruding, and self-drilling variants
• Manufactured from carburized steel (99% of production) with optional stainless steel or non-ferrous metals
• Heat-treated for optimal performance - carbon steel screws are carburized, stainless steel screws are solution-hardened
• High surface hardness with tough core ("soft outside steel") for superior fastening performance
• Surface protection through plating or phosphate treatment (phosphating)
• Produced using high-speed cold heading machines for precision forming

The main differences between SUS304 and SUS316 stainless steel are as follows:
Composition: SUS304 contains 18% chromium and 8% nickel, while SUS316 adds about 2% molybdenum on top of that, which makes 316 stronger in terms of corrosion resistance.

Corrosion resistance: SUS316 excels in marine environments and the chemical industry, especially in chloride corrosive environments. And SUS304 performs well in general corrosive environments.

High temperature performance: SUS316 has better high temperature resistance and is suitable for high temperature and high pressure environments.

Applications: SUS304 is widely used in food, chemical and medical devices, etc., while SUS316 is more suitable for demanding applications such as marine and chemical industries.
 

These differences make it necessary to decide whether to use SUS304 or SUS316 when choosing stainless steel materials based on specific usage requirements.

Available packaging options include small packing, carton packing, and pallet configurations. Standard package quantity is 100 pieces, with custom packaging solutions available upon request.