Fixed cutter drill bit heel and back-ream cutter protections for abrasive applications

A drill bit, comprising:

• a bit body having a longitudinal axis and a cutting face;
• a plurality of blades spaced azimuthally about the cutting face and extending at least laterally through a gage region and terminating at a heel surface;
• a plurality of cutters disposed along the blades;
• and
• at least one back reaming element disposed on the heel surface of at least one blade;
• wherein the at least one blade comprises a first matrix material extending from the heel surface to a distance below the at least one back reaming element and a second matrix material adjacent to the first matrix material.

A fixed cutter drill bit, comprising:

• a bit body having a longitudinal axis and a cutting face;
• a plurality of blades spaced azimuthally about the cutting face and extending at least laterally through a gage region and terminating at a heel surface;
• a plurality of cutters disposed along the blades;
• and
• at least one back reaming element disposed on a heel surface of at least one blade.