Alloy Type: A5.21, COBALT Bare Electrodes and Rods for Surfacing
Alloy ERCOCR-A is recommended for cases where wear is accompanied by elevated temperatures and where corrosion is involved, or both.  Cobalt alloys are inherently good for resisting metal-to-metal wear, particularly in high load situations that are prone to galling.
Typical Applications:
Automotive and fluid flow valves
Chain saw guides
Hot punches
Shear blades
Extruder screws
AWS Specification
A5.21/A5.21M:2011
AWS Classification ERCOCR-A
Welding Current DC
Typical Wire Chemistry
C 0.9-1.4
Mn 1.0
Si 2.0
Cr 26-32
Ni 3.0
Mo 1.0
Fe 3.0
W 3.0-6.0
Co Rem
OTHER 0.50
Typical Mechanical Properties
(As Welded)
Yield Strength: Castings 101.5 ksi, Cobalt HS-6 109 ksi
Tensile Strength: Castings 123 ksi, Cobalt HS-6 183.5 ksi
Elongation%:  Castings <1, Cobalt HS-6 3-5
Typical Hardness for multilayer welds, 23-47 HRC
Welding Positions
Mig:  Flat
Tig:  All