Iron Power (Fe) has many types like Atomised Iron Powder, Sponge Iron Powder (Reduced), etc… It finds majority of consumption in Powder Metallurgy / Sintered Parts applications.
Both types differ in their properties due to particle shape and size. Atomised type has higher density and compressibility which is good for parts requiring good sintered density and strength. Sponge type has higher green strength and lower density which is good for parts requiring porosity (self-lubricating bushes) and higher strength during compaction (Thin walled or complex shape components). Atomized and Sponge can be mixed together to achieve properties demanded by specific applications.