Used primarily for welding
similar wrought or cast 25%Cr-20%Ni (310) parent
alloys with up to 0.25% carbon. For maximum resistance
to solidification cracking and micro fissuring, the Mn version
weld metal manganese range is raised to 2-5%.
The high alloy content of type 310 gives useful
oxidation resistance up to peak temperatures of about
1200°C for heat shields, furnace parts and ducting.
These consumables can also be used for mixed welding
and dissimilar joints including those where PWHT is
applied, but it should be noted that the relatively high
thermal expansion coefficient may promote thermal
fatigue in transition joints which are subject to thermal
cycling. In such cases, nickel base consumables are
usually preferred.
Other uses include buffer layers and for surfacing.
The fully austenitic weld metal can be useful for
specialized applications requiring low magnetic
permeability (typically <1.01). 310 weld metals are
also inherently tough down to –196°C and therefore
suitable for cryogenic installations. No preheat required. Preferably keep interpass
temperature below 150°C and heat input below
1.5kJ/mm; this is particularly important for high
heat input processes e.g. SAW.