Oerlikon Inertfil 16 6 1 description: INERTFIL 16 6 1 is used mainly for soft-martensitic steel applications in hydro turbine engineering (pumps and turbines). Microstructure of the weld metal is martensitic with 5 to 20% austenite in the martensitic matrix. INERTFIL 16 6 1 can be used in the same environment as the martensitic steels with 13% or 17% chromium, but can withstand higher concentration and higher temperatures.