you can put oil on the surface and let it burn in an oven at 400 to 450 degrees. this smells up the house, and will make you wife very angry. try quenching in oil instead of water during HT. you can also heat the blade to about 400 and use beeswax, mixed with old motor oil, and rub it on to the hot blade letting it burn and blacken, this leaves a more "orc" finish. you can also get teflon, and gun kote from brownells.com. this cure at temp. in the 100 to 200 degree range, and can be done in an oven.you can let the make the blades rust completely then sand them with a random orbital lightly, and it leaves a slightily silver/black finish with cool pitting patterns. basically it has a polished forge finish.
if i might sugest it, blackening the handles would make it match the blades better once they are black. you might accomplish this with some wax and a propane torch, just heat the wax a bit, rub it thickly on the handle, the heat the handle with the torch, allowing the wax to soak and blacken, then wipe it with a rag. you can do this method with patroleum jelly, but it doesnt get as dark, and if you apply to much, it will leave a slippery handle. you should was the leather with a little warm water and soap, after melting the jelly into the leather, but let it cool first, then work it a bit, then you can was it if its greasy.