Bohler Fox C 9 MVW ( Creep Resistant) Low Alloy Steel Stick Electrodes
Bohler Fox C 9 MVW is a shielded electrode with a basic coating and a core wire alloy, designed for manual arc welding (SMAW).
The weld metal, of type 9Cr-1Mo-1W-VNb, exhibits a fully tempered martensitic microstructure with suitable mechanical properties after post-weld heat treatment.
Scope of application: This standard covers the fusion welding of similar alloyed ferritic steels with enhanced creep resistance, such as ASTM 911 (E 911) grade pipes, tubes, forgings, and castings. These materials are used primarily in the thermal power industry, approved for long-term service at temperatures up to 650 °C .
The chemical composition has been optimized to achieve high creep resistance and ductile weld metal following post-weld heat treatment. At the same time, trace elements have been kept at low levels, ensuring a low level of diffusive hydrogen in the weld metal.
Features
- Highly stable arc with minimal spatter in all positions except vertical down (PG/5G down). Slag detaches cleanly, ensuring smooth multi-pass execution.
- Requires strict preheating parameters and interpass temperatures matching P911 specifications (typically 200–300°C).
- Final material attributes depend entirely on Post-Weld Heat Treatment tempering, typically requiring annealing around 760°C for 2 hours to reach optimum mechanical ductility.
Technical Data
- AWS A5.5 / SFA-5.5: E9015-B92 H4 (modified)
- EN ISO 3580-A: E ZCrMoWVNb 9 1 1 B 4 2 H5 []
- Approved for long-term continuous service at temperatures up to 650°C.
- Alloying Characteristics: Tungsten (W) alloyed to ensure supreme creep rupture strength and long-term thermal stability compared to standard non-tungsten 9Cr electrodes (like the standard C 9 MV variant).
- Purity: Highly restricted traces of accompanying impurities and a low diffusible hydrogen level (H5) to strictly resist cold-cracking
Datasheet