Alloy Type: A5.21, COBALT Bare Electrodes and Rods for Surfacing
Alloy ERCOCR-E electrodes and rods have very good strength and ductility in temperatures up to 2100 degrees F.  Deposits are resistant to thermal shock and oxidizing and reducing atmospheres.  The deposit is a solid solution strengthened alloy with a relatively low weight-percent carbide phase in the microstructure.  Hence, the alloy is very tough and will work harden.
Typical Applications
Automotive exhaust valves
Steam Valves
Hot Shears
Forging Dies
AWS Specification
A5.21/A5.21M:2011
AWS Classification ERCOCR-E
Welding Current DC
Typical Wire Chemistry
C 0.15-0.45
Mn 1.5
Si 1.5
Cr 25-30
Ni 1.5-4.0
Mo 4.5-7.0
Fe 3.0
W .50
Co Rem
OTHER 0.50
Typical Mechanical Properties
(As Welded)
Yield Stress Rp(0.2%):  Castings 82 ksi, Cobalt HS-1 87 ksi
Tensile Strength:  Castings 103 ksi, Cobalt HS-1 145 ksi
Elongation%:  Castings 9, Cobalt HS-1 20
Hardness: 20-35 HRC
Welding Positions
Mig:  Flat
Tig:  All