General Characteristics
N'GENIUS 316LM4N™ are general purpose alloys that retain all the benefits of conventional 316L austenitic stainless steels in terms of ductility, sub-zero and cryogenic temperature toughness and excellent weldability, but with significantly higher strength properties and vastly improved resistance to general and localised corrosion.
To support the rapidly growing hydrogen market, N'GENIUS 316LM4N H2™ Alloy Types and Variants have been developed as part of the N'GENIUS H2 SeriesTM. Their chemical compositions have been specifically formulated to give a more stable single-phase austenitic microstructure – a key requirement for both gaseous and liquid hydrogen applications.
Market Positioning
The N'GENIUS 316LM4N™ alloys should be considered as direct replacements for conventional 316L and 316LN, where applicable.
N'GENIUS 316LM4N H2™, with a more stable single phase austenitic microstructure, should be considered as a replacement for conventional 316L for use across a wide range of hydrogen applications.
Alloy Types and Variants
N'GENIUS 316LM4N™ includes a number of Alloy Types and Variants, offering flexibility and choice for engineers. These include:
- N'GENIUS ICONIC 316LM4N™
- N'GENIUS INFINITY 316LM4N™
- N'GENIUS 316LM4N H2™
The chemical compositions of the ICONIC variants are formulated to achieve distinct minimum specified levels of PREN and various pre-determined levels of Chromium and Nickel, to suit specific service conditions and process applications.
Whilst the chemical compositions of the INFINITY variants, which can be manufactured to contain additional alloying elements including Copper and Tungsten, as well as various pre-determined levels of Chromium and Nickel, are formulated to achieve distinct minimum specified levels of PRENW to further improve the overall corrosion performance in an even wider range of service conditions and process environments.
Performance Benefits
The performance benefits of the N'GENIUS ICONIC 316LM4N™ Alloy Types and Variants include:
- Unique combination of mechanical and corrosion resistance properties
- Higher mechanical strength properties compared to conventional austenitic stainless steels
- Higher allowable design stresses enable improved safety to be built into system design
- Reduced wall thicknesses can lead to weight savings, reduced transport costs and reduced fabrication time, which in turn results in less CO2 emissions and an overall reduction in construction and project costs
- Excellent ductility due to a more stable single-phase austenitic microstructure
- Excellent toughness at sub-zero temperatures associated with upset service conditions and at cryogenic temperatures
- Non-magnetic condition
- Improved Minimum Pitting Resistance Equivalent Values (PREN)
- Superior resistance to Localised Corrosion (Pitting Corrosion, Intergranular Corrosion and Microbially Induced Corrosion) in a wide range of service conditions and process environments
- Superior resistance to General Corrosion in various environments
- Superior resistance to Hydrogen Embrittlement due to a more stable single-phase austenitic microstructure
- Improved resistance to Chloride Stress Corrosion Cracking in a wide range of service conditions and process environments
- Improved Sustainability
Additionally, the N'GENIUS 316LM4N H2™ alloy offers:
- More stable, single-phase austenitic microstructure at sub-zero temperatures for use with gaseous hydrogen (typically -60°C or below) and cryogenic liquid hydrogen temperatures (-253°C) as required by International codes and standards
- Greater resistance to hydrogen embrittlement by suppressing ferrite and martensite formation.
* Typical Mechanical Properties
* Mechanical properties shown above are for wrought products in the solution heat treated condition and may vary subject to alloy composition, product form and product route. For illustrative purposes only.
| Alloy Type |
Tensile Strength
(min) |
Yield Strength
(min) |
Elongation
(min) |
PREN
(min) |
|
Ksi |
MPa |
Ksi |
MPa |
% |
|
| N'GENIUS ICONIC 316LM4N™ |
102 |
700 |
55 |
380 |
40 |
≥35 |
| N'GENIUS INFINITY 316LM4N™ |
102 |
700 |
55 |
380 |
40 |
≥37.5 |
| N'GENIUS 316LM4N H2™ |
102 |
700 |
55 |
380 |
40 |
≥37.5 |
| 316L |
70 |
485 |
25 |
170 |
40 |
≥23 |
| 316LN |
75 |
515 |
30 |
205 |
40 |
≥24 |
Advantages
The unique combination of mechanical and corrosion resistance properties of N'GENIUS 316LM4N™ provides end users and engineers with a range of advantages:
- Excellent all-round general-purpose grade which can be manufactured in a vast range of products and utilised in a wide range of markets, industries and applications
- The increased strength in the solution heat treated condition offers the potential to significantly reduce wall thicknesses of products and systems, leading to weight reduction and lower fabrication, construction and transportation costs and an overall reduction in project costs
- Significantly increased resistance to general and localised corrosion (Pitting Corrosion and Intergranular corrosion) for welded products and fabrications in a wide range of environments
- Significantly improved toughness for products utilised in sub-zero and cryogenic applications
- Can be manufactured and supplied in the cold worked or cold formed condition to further enhance the minimum mechanical properties for architectural or structural applications
Industries
- Architectural
- Automotive
- Chemical Process
- Construction
- Food and Beverage
- General Engineering
- Hydrogen
- LNG and FLNG
- Nuclear
- Oil and Gas
- Pharmaceutical
- Water Treatment
Applications
The N'GENIUS 316LM4N™ Alloy Types and Variants can be manufactured in cast and wrought product forms for all primary products, secondary products, engineering products and fabricated products. Typical applications include pipelines and piping systems (pipes, fittings, flanges), fasteners, manifolds and headers, pumps, valves, filtration systems, storage tanks and vessels providing a total system material.
The N'GENIUS 316LM4N H2™ Alloy Types and Variants can be manufactured and supplied for the above mentioned product applications which are used for various hydrogen applications including hydrogen production systems, hydrogen transportation and storage, hydrogen mobility and high pressure hydrogen fuel cell and refueling systems.
N'GENIUS INFINITY Series™
N'GENIUS 316LM4N™ Alloy Types and Variants are also available in the N'GENIUS INFINITY Series™, where they can be manufactured to contain additional Alloying Elements (Copper, Tungsten, etc.) to further improve the overall corrosion performance in a wider range of service conditions and process environments.
The chemical compositions of the N'GENIUS INFINITY 316LM4N™ Alloy Types and Variants can also be formulated to achieve distinct minimum specified levels of Pitting Resistance Equivalents PRENW ≥ 37.5 or PRENW ≥ 40, further improving their resistance to general and localised corrosion.