DS EN 4630:2008 Aerospace Series - Steel Fe-Pm 3504 (X4crnimo16-5-1) - Air Melted - Hardened And Tempered - Forgings - D[E] <= 200 Mm - 900 Mpa <= R[M] <= 1050 Mpa Describes the requirements relating to: Steel FE-PM 3504 (X4CrNiMo16-5-1) - Air melted - Hardened and tempered - Forgings - D[e] <= 200 mm - 900 MPa <= R[m] <= 1050 MPa, for aerospace applications.