What is Duplex Stainless Steel? What sets it apart from regular stainless steel?
The word duplex itself rings a bell in coherence with the term- “dual”. Just as its name suggests, duplex stainless steel is an alloy with dual microstructural integrity. Stainless Steel Alloys are generally found in three main types:
- Austenitic Stainless Steel
- Martensitic stainless steel
- Ferritic
Duplex Stainless Steel was discovered by combining Austenitic SS along with ferritic SS. This amalgamation led to the production of Duplex and Super Duplex Stainless steel.
Duplex SS can also be used to forge a variety of components such as round bars, wires, mesh nets, flat bars, screws, fasteners, etc.
Does your upcoming project demand the use of Duplex SS fasteners? Let’s have a look.
Firstly, let us take a glance at the metallurgic composition of Duplex 31803 (F51) fasteners.
Duplex Stainless Steel contains elements such as:
The regular iron, chromium, and nickel along with molybdenum, iron, copper, and nitrogen for enhanced properties.
Benefits of Duplex Stainless Steel Fasteners
- Strength and durability:
It is tested and proven that when compared to austenitic grades and ferritic grades of stainless steel, duplex SS fasteners are up to two times stronger, durable, and reliable.
- Tough and Ductile:
Duplex SS Fasteners are extremely tough and can withstand extreme conditions with ease. The ferritic composition imparts great strength and the austenitic microstructure develops its ability to resist corrosive media for sustained periods of exposure.
- Anti-Corrosive:
As mentioned earlier, Duplex SS fasteners due to their austenitic phase can withstand and resist severe corrosive environments. Due to the unique additions of nitrogen and molybdenum, Duplex fasteners withstand chloride pitting and crevice corrosion with ease.
- Cost-effective:
With the benefits they bring, duplex graded stainless steel fasteners are worth the money spent. They are highly cost-efficient when compared straight up with various other grades of Stainless Steel fasteners. Additionally, one can rely on a stainless steel fastener to work for numerous years with zero maintenance or service.
What are the applications that rely on duplex fasteners the most?
Generally, duplex fasteners can be used in place of SS 316 fasteners. However, the roles cannot be reversed. When an application demands exclusively for Duplex SS, it cannot be compromised.
Given below are a few applications that utilize duplex SS fasteners:
- Seawater applications
- Offshore drilling
- Desalination plants
- Pulp and paper factories
- Construction
- Chemical industries
- Naval and Shipbuilding industries
- Aircraft equipment, etc.
