The present invention provides a low-melt nickel-based alloy powder applied in an activated diffusion brazing repair on gas turbine components. In one embodiment, and by way of example only, the low-melt alloy powder comprises between about 6.7% and about 9.2% by weight Cr, between about 9.7% and about 10.3% by weight Co, between about 3.7% and about 4.7% by weight W, between about 3.3% and about 6.3% by weight Ta, between about 3.6% and about 5.2% by weight Al, between about 1.3% and about 4.0% by weight Hf, between about 0.02% and about 0.06% by weight C, between about 1.0% and about 3.2% by weight B, and Ni. Optionally, the low-melt alloy powder may include between about 1.4% and about 3.2% by weight Re.