Hot Black Oxide

EPI manufactures a variety of conventional hot oxide processes for blackening iron, steel, hardened tool steel, cast iron, forged steel, stainless steel, copper, brass, cadmium, die cast zinc and electroless nickel. Call us at 262-786-9330  for assistance in selecting the black oxide best suited for your metal blackening needs. Questions about Black Oxide? Read our Black Oxide FAQ.

EPi’s Ultra-Blak 400 process - The best performing black oxide process because:

• Ultra-Blak 400 is a premium grade black oxide formulation that actually costs
  less to apply.
• There is no rub-off as is common with other black oxide processes.
• Faster blackening reaction for reduced immersion time.
• Blacker finish and greater depth of blackness.
• 20% to 30% less salt consumption than with other black oxide processes.
• User friendly with a wide window of operation.
• Blackens a wider range of steel alloys in the same bath with less rejects than competitive baths.
• Frequently operated at a temperature as low as 272°F.
• Only uses 5.75 pounds of Ultra Blak salts are used per gallon of water versus
  the 7-8 pounds used in other black oxide processes.
• Its unique wetting agent produces a more uniform black finish and a quicker reaction. The reduced viscosity ensures complete coverage of all surfaces.
• Complies with and exceeds the requirements of military specification MIL-C-13924C and AMS-2485. It meets and exceeds the oxalic acid test and salt spray requirements.

Black Oxide Advantages

• No dimensional change (paint builds up)
• Reduces handing of parts- many parts can be done in a rotating barrel
• No primer or precoat phosphate required
• No bake oven - no volatile organic fumes
• Less equipment and less maintenance of equipment
• Higher productivity – less setup and less processing time

EPI’s Hot Black Oxide Chemicals

Ultra-Blak 400 for Steel Black oxide (Fe304 - Magnetite) finishes are produced on steel surfaces with this mixture of alkaline salts and oxidizing agents combined with penetrants, catalysts, activators, rectifiers and wetters. Salts are used at 5.75 pounds per gallon of water at a temperature of 285° F. Complies with military specification MIL-DTL-13924D Class 1 and AMS 2485H. Comes in 50lbs, 125lbs or 500lbs.

Ultra-Blak 400-L for Steel A highly concentrated liquid version of Ultra-Blak 400 which is recommended for black oxide installations where it is desired to automate the replenishment addition of the blackening salts solutions through a pump and liquid level control system. It is also ideal for the initial charging of black oxide baths which will be replenished with the powdered Ultra-Blak 400. Comes in 5 gallon pail or 55 gallon drums.

Ultra-Blak 404 for Cast Iron — This black oxide is the preferred oxidizing salt mixture for blackening cast iron, malleable iron as well as some mild low carbon steels. Concentration of 4.75 pounds per gallon of water at temperatures of 250° to 260° F.

Ultra-Blak 407 for Stainless Steel — Black oxide finish for stainless steels. Oxidizing salts used at 4.75 pounds per gallon of water at temperatures of 250° to 260° F. The finishes comply with military specification MIL-DTL-13924D Class 4. The versatile solution may also be used to blacken malleable and cast iron as well as some mild low carbon steels.

Ultra-Blak 420 for Copper/Brass — This black oxide is an oxidizing salt mixture for blackening copper, brass and bronze. Used at a concentration of 2 pounds per gallon of water at temperatures of 200° to 210° F to blacken copper surfaces with a deep black, abrasion resistant finish. It must be used in conjunction with EPI's E-Prep 220 brass activator to blacken high zinc (15% to 35% zinc) copper alloyed surfaces.

Ultra-Blak 455 for Cadmium/Zinc — Black oxide finish for cadmium and zinc. Liquid concentrate used at 25% by volume in water at temperatures of 120° to 160° F.

Ultra-Blak 460 for Zinc — A non-chromated black oxide chemical conversion finish for die cast and plated zinc surfaces. Salts used at 6 to 8 oz. per gallon of water and temperatures of 150° to 170° F.

Ultra-Blak 465 for Nickel and Electroless Nickel— Black oxide chemical conversion finish for nickel plated surfaces. Liquid two component concentrates used at a total volume of 25% by volume in tap water at temperatures of 160° to 180° F.

Ultra-Blak Rectifier — Additive for black oxide solutions to control the buildup of excessive red iron oxide and copper which cause off colored reddish finishes. Liquid concentrate used at 0.5 to 1 ounce per gallon of oxide solution.

Additional Metal Blackening and Black Oxide Chemicals:

• Insta-Blak 333 for Iron and Steel
   
• Insta-Blak for Zinc, Aluminum and Stainless Steel
   
• Insta-Blak Z-360 for Zinc
• Insta-Blak SS-370 for Stainless Steel
• Insta-Blak S-334 swab-on for Steel
• Insta-Blak A-380 for Aluminum
• Insta-Blak A-384 for Aluminum
• Insta-Blak A-385 for Aluminum