Chromium-containing cemented carbide body having a surface zone of binder enrichment

A coated cutting insert comprising:

• a rake face and a flank face, a cutting edge at the juncture of the rake face and the flank face;
• the cutting insert having a hard refractory coating and a substrate wherein the coating is adherently bonded to the substrate;
• the substrate comprising a tungsten carbide-based material comprising a bulk composition of at least about 70 weight percent tungsten and carbon, between about 3 weight percent and about 12 weight percent cobalt, and at least 0.09 weight percent chromium;
• the cobalt and the chromium forming a binder alloy:
• wherein the binder alloy content being enriched in a surface zone of binder alloy enrichment beginning near and extending inwardly from a peripheral surface of the substrate;
• and
• wherein the bulk composition of the substrate further comprises tantalum in an amount up to about 10 weight percent, niobium in an amount up to about 6 weight percent, and titanium in an amount up to about 10 weight percent.