Powder metallurgy is known to be a cost effective technology to manufacture components with narrow tolerances in combination with required mechanical properties. A key aspect is the sintering process. Through control and creation of internal stresses guided by the sinter hardening atmosphere give you properties that even outperform sintered and case hardened properties at considerable lower cost. Creation and control of such atmosphere is essential to increase the competiveness of the PM technology. In this paper concepts for carbon control and carbon gradient are presented and described in terms of how to create it through addition and measurements. Influences of created internal stresses by the atmosphere on PM applications are presented.