1. n. [Drilling]

A process in which a wear-resistant alloy is applied to the tool joints of drillpipe or drill collars to prolong the life of oilfield tubulars. Hardbanding is applied where rotational and axial friction associated with drilling and tripping create excessive abrasive wear between drillstring and casing, or between drillstring and rock. Hard alloy overlays are applied to the points of greatest contact, typically using advanced welding techniques. Typical alloys used in this process range from ultra-wear resistant tungsten carbide, to less abrasive chromium carbide, titanium carbide and borides. Some hardbanding processes take a different approach to reducing wear in tubulars, using materials that achieve a low coefficient of friction used to protect the drillstring from abrasion. 

See: tool joint,  upset,  hardfacing