BÖHLER M789


The M789 – Precipitation Hardenable Stainless Steel – BÖHLER material, combines the easy printability of a Maranging Steel with the corrosion resistance of a 17-4PH (Stainless Steel AISI630).

The M789 reaches high tensile strength (up to 1800 MPa) and hardness values (up to 52HRC) after heat treatment, which makes usable for structural components that usually where made using high performance structural steels, such as AISI 4340 and Maraging M300.

Furthermore, the M789 steel is a corrosion resistance steel rather than other high performance structural steels, hence it is possible to avoid to use galvanic coatings (e.g. cadmium and chromium, VI and III).

These properties allow to use the M789 steel for shafts, brackets, dies, gears and impellers operating in mild to heavy corrosive environments.

Mechanical Properties Test Method As Built Heat Treated
Yield Modulus EN ISO 6892-1 175-185 GPa 185-195 GPa
Yield Strength (Rp 0.2%) EN ISO 6892-1 700-800 MPa 1390-1710 MPa
Tensile strength EN ISO 6892-1 1000-1040 MPa 1570-1800 MPa
Elongation at Break EN ISO 6892-1 7-14 % 2-6 %
Charpy V-notch test EN ISO 148-1 - 6-14 J
Hardness EN ISO 6508-1 20-30 HRC 52-58 HRC
Chemical Composition and Physical Properties    
Chemical composition C
Cr
Ni
Mo
Al
Ti
< 0,02 %
12,2 %
10 %
1 %
0,6 %
1 %
Physical Properties Density 7,85 g/cm3