ASTM International (formerly American Society for Testing and Materials) develops and publishes technical standards for a wide range of materials, products, systems, and services. For stainless steel angles, several ASTM standards are relevant, primarily governing the material composition, mechanical properties, manufacturing tolerances, and general requirements.

The most commonly cited ASTM specifications for stainless steel angle bars are:

• ASTM A276 / A276M: Standard Specification for Stainless Steel Bars and Shapes. This is a primary standard covering hot-finished or cold-finished bars, including angles. It specifies requirements for various stainless steel grades regarding chemical composition, tensile properties, hardness, and heat treatment.
• ASTM A479 / A479M: Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels. While oriented towards pressure vessel applications, the grades and requirements often overlap with A276 and may be specified for angles intended for demanding structural or high-temperature applications.
• ASTM A484 / A484M: Standard Specification for General Requirements for Stainless Steel Bars, Billets, and Forgings. This standard covers aspects not detailed in the specific product specifications like A276, such as permissible variations in dimensions (tolerances for size, straightness, and angularity), marking requirements, testing procedures, and packaging.

When ordering or specifying stainless steel angles, referencing the appropriate ASTM standard (e.g., “Stainless Steel Angle, 304/304L, per ASTM A276 and A484”) ensures the product meets established criteria for quality and performance.

These standards define critical parameters, summarized below:

Parameter Defined by ASTM Standards	Significance
Chemical Composition	Ensures the correct grade is supplied, dictating corrosion resistance, weldability, and other material characteristics.
Mechanical Properties (Tensile Strength, Yield Strength, Elongation)	Guarantees the material meets the required strength and ductility for structural integrity.
Dimensional Tolerances (Size, Length, Straightness, Angularity)	Ensures the angle bar conforms to the expected physical dimensions for proper fit and assembly (often detailed in A484).
Heat Treatment / Condition	Specifies the processing state (e.g., annealed), which affects mechanical properties and machinability.
Finish (e.g., Hot-Rolled, Annealed, Pickled)	Defines the surface condition of the angle bar.

Adherence to these ASTM standards is crucial for ensuring product consistency, safety, and suitability for the intended application.