Avesta FCW 308L/MVR-PW description: AVESTA FCW 308L/MVR-PW is designed for welding austenitic stainless steel type 19 Cr 10 Ni or similar. The filler metal is also suitable for welding titanium and niobium stabilised steels such as ASTM 321 and ASTM 347 in cases where the construction will be operating at temperatures below 400°C. For higher temperatures a niobium stabilised consumable such as AVESTA FCW 347/MVNb is required.