API Reference > physical-material-backend > PhysicalMaterial PhysicalMaterial A PhysicalMaterial defines the matter that makes up physical elements. Classes Name Description Aggregate Aggregate is a bis:PhysicalMaterial representing a broad category of coarse to medium grained particulate material typically used in construction as Aluminum Aluminum is a bis:PhysicalMaterial representing aluminum (atomic symbol Al) or one of its alloys. Asphalt Asphalt is a bis:PhysicalMaterial representing a mixture of a bituminous binder and aggregates. Concrete Concrete is a bis:PhysicalMaterial representing a mixture of hydraulic cement, aggregates, water and optionally other materials. PhysicalMaterialSchema The PhysicalMaterialSchema contains standard physical material classes. Steel Steel is a bis:PhysicalMaterial representing an alloy of iron, carbon and other elements. Last Updated: 15 June, 2021