SSMATERIAL FAMILY
Stainless Steel
Stainless steels are iron-based alloys whose chromium-rich surface film provides corrosion resistance. The exact grade determines how they perform in a particular environment.
What defines it
- A protective passive surface film
- Several distinct metallurgical families
- Grade-dependent corrosion performance
Understand the distinction
Stainless steel describes more than one kind of steel. Its chromium-rich passive surface film is the common basis of corrosion resistance, while its internal structure separates austenitic, ferritic, martensitic and duplex families. Those differences help explain why two stainless materials can have different mechanical and fabrication behaviour.
DXMATERIAL FAMILY
Duplex Steel
Duplex stainless steels combine austenitic and ferritic structures. They are considered where strength and corrosion resistance are both important to the design.
What defines it
- Austenitic-ferritic structure
- Strength and corrosion resistance considered together
- Grade-specific selection
Understand the distinction
Austenite and ferrite are two structures found within duplex stainless steel. Their combination gives duplex its name and its distinct balance of strength and corrosion behaviour. Composition and fabrication affect the finished material, so the presence of two phases does not make every duplex grade identical.
SDMATERIAL FAMILY
Super Duplex
Super duplex steels are highly alloyed members of the duplex stainless family, considered for demanding combinations of corrosion resistance and mechanical strength.
What defines it
- A duplex stainless structure
- Higher alloying for demanding corrosion conditions
- Performance defined by the selected grade
Understand the distinction
Super duplex keeps the two-phase structure of duplex stainless steel rather than forming a separate base-metal family. Its higher alloying is developed for increased corrosion resistance alongside mechanical strength. The family description explains that approach, but the selected grade and finished component still define the resulting properties.
NiMATERIAL FAMILY
Nickel Alloys
Nickel alloys cover several alloy systems developed for specific combinations of corrosion resistance, heat resistance and mechanical properties.
What defines it
- Several distinct alloy systems
- Chemistry-specific corrosion behaviour
- Different strength and heat-resistance profiles
Understand the distinction
Nickel can be combined with chromium, molybdenum, iron, copper and other elements to create different alloy systems. Changing that combination changes the balance of corrosion behaviour, heat resistance and mechanical properties. This is why a nickel-alloy family name does not describe one uniform material.
CSMATERIAL FAMILY
Carbon Steel
Carbon steels are iron-based materials whose composition and processing influence strength, toughness and fabrication behaviour. The specified grade is central to the fitting requirement.
What defines it
- Composition-dependent properties
- Material condition matters
- Grade-specific fabrication requirements
Understand the distinction
Carbon steel is a broad iron-based material family. Carbon and manganese content influence its properties, while processing and material condition also affect strength, toughness and fabrication behaviour. The family name is useful for classification, but it does not describe one fixed set of properties.
ASMATERIAL FAMILY
Alloy Steel
Alloy steels use additions such as chromium, molybdenum, nickel or vanadium to develop particular properties. Different alloy systems require different material and fabrication controls.
What defines it
- Properties tailored through alloying
- Composition and condition both matter
- Weldability varies between grades
Understand the distinction
Alloy steels use additions such as chromium, molybdenum, nickel or vanadium to develop particular properties. Their composition and heat-treated condition work together to influence mechanical behaviour. The same broad family also includes materials with different welding behaviour, rather than one common fabrication response.
Titanium’s corrosion behaviour is closely linked to its protective oxide film. Suitability depends on the selected material and the actual chemical environment.
What defines it
- Protection from an oxide surface film
- Environment-dependent corrosion behaviour
- Selection based on the actual process conditions
Understand the distinction
Titanium forms an adherent oxide film that protects the underlying metal in many environments. Its corrosion behaviour changes when conditions maintain or attack that film. Understanding this surface mechanism explains why a general corrosion-resistance description cannot describe titanium’s behaviour in every chemical environment.
CuMATERIAL FAMILY
Copper Alloys
Copper alloys include distinct groups such as brasses, bronzes and copper-nickels. Their properties and suitability depend on the specific alloy system.
What defines it
- Multiple copper-based alloy systems
- Properties vary with composition
- Exact material designation is essential
Understand the distinction
Brasses, bronzes and copper-nickels are distinct groups within the copper-alloy family. Alloying copper changes mechanical, physical and corrosion properties, so the shared base metal does not make these groups equivalent. Even a familiar name such as bronze describes a family rather than one unique composition.
＋MATERIAL FAMILY
Project-Specific Materials
Some projects define the material through a customer specification, a controlled drawing or a requirement that does not fit a broad catalogue family.
What defines it
- A customer or project-controlled requirement
- Clear document hierarchy and revision
- Supply against the complete customer specification
Understand the distinction
Project-specific describes how a material requirement is controlled, rather than one internal structure or alloy chemistry. A customer specification or drawing may define composition, condition, material designation and acceptance criteria. Those defined requirements are more precise than a broad catalogue family name.
Family descriptions are qualitative. Exact composition, grade, condition and exposure determine the material requirement.
