Phosphorus dissolves in γ iron to about 0.5% α-iron to about 2.5%, mostly as a whole is dissolved in ferrite.
Increases hardenability in steels and in low carbon steels increases hardness and strength and resistance to corrosion.
The amount of phosphorus in steels with higher carbon content is intentionally reduced because of the contributing to
the embrittlement of steel. The addition of phosphorus in an amount up to 0.1% is used in the production of easy
machining steel which improves machinability. In the composition of any other steel it should not be more than 0.05%
and in steels with higher-quality steels to 0.03% and sometimes less because Phosphorus causes fragility.
