The effect of pore size and heat treatment on the fracture toughness of pressed and sintered Ancoloy SA powdered steel

Ancoloy SA powder, adjusted by addition of carbon to give a composition which was slightly hypo-eutectoid, was tested in a pressed and sintered condition. Porosity was varied by changing the pressing pressure and structure was varied by heat treatment. The effect of pressing pressure, through void content and shape, dominated the toughness change, although heat treatment produced a large in yield stress.