Tungsten Carbide is available in two different forms for addition to weld puddles to produce a hard, wear-resistant overlay. Either cast/crushed or sintered pellets.
The cast/crushed is generally harder (it has no binder) but is very angular and contains sharp edges that will agressively cut any steel it comes into contact with (such as casing). The cast/curshed also has a higher melting point, so it will dilute less in the weld pool during application.
The sintered pellets are a little softer, but are rounded, so they will not be as agressive. They do have a lower melting point and will dissolve a bit more in the weld pool.
Either one is considered very hard and will provide resistance to wear against rock. For maximum wear resistance, use cast/crushed, but understand that it will tear-up any casing it is run in.
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