CODIAC - Nickel Silicon Carbide Overview


Nickel Silicon Carbide (CODIAC) is a regenerative layer of an electrolessly plated matrix, usually a nickel/phosphorus alloy, with finely divided particles uniformly dispersed in it. The particles are uniform in size and the coating contains 30% carbide by volume. The nickel matrix alloy most commonly used is made up of 90-93% nickel and 7-10% phosphorus.

What will CODIAC do for me?

Quite a bit. CODIAC in a relatively thin layer (0.5 to 2 mil) will provide maximum protection for your substrates against extreme wear and corrosion. Since your coated machinery parts will last much longer, reduced maintenance and production costs can be realized. Fewer replacement parts will be required, and lost time incurred through machine shut down will be minimized.

How expensive is CODIAC?

The cost of CODIAC is relatively low when consideration is given to its outstanding wear life, and savings that can be realized from extended use and greater reliability.

After the coating is applied are there any other steps to the process?

Sometimes. When coating metallic substrates, a heat treatment step is generally desirable to provide improved adhesion of the coating, hardness of the matrix and improved wear. Baking temperatures range from 450 degrees to 750 degrees depending on the substrate.

What substrates can be coated?

Any of the aluminum series, carbon steel, tool steel, stainless steel and brass are suitable as substrates.

What are some suitable applications for CODIAC?

Too many to list them all. Included among the successful field applications may be found:

  • Mechanical shaft shields for automotive water pumps and chemical process pumps.
  • Textile machinery parts.
  • Tools for processing glass or ceramic filled resin.
  • High speed paper handling equipment such as lifters, sorters and guides.
  • Ultrasonic transducer wear plates.
  • Gage blocks.
  • Smokeless powder extruder dies and cutters.
  • Industrial scissors and barber scissors.
  • Injection molding, extrusion, and compression molding for processing glass filled resins
What advantages can CODIAC provide over other coatings?
  • First, Hardness CODIAC provides exceptional hardness.
  • Next, Surface Coverage - Inherent as part of the electroless plating technique, uniform plating is achieved even in fine recesses without the use of complicated electrolytic and spray coating techniques. In addition, the matrix used in CODIAC provides excellent corrosion resistance.
  • Finally, Extended Lifetime - CODIAC affords significantly increased durability in comparison to conventional wear surfaces such as tool steel, mild steel and hard coatings such as chromium, silicon carbide, chromium dioxide spray, etc.

Technical hardness data for Codiac and other materials

Material Knoop Rockwell C
Nickel Silicon Carbide 3,300  
Silicon Carbide 2,500  
Hard Chrome 972 70
Tool Steel (hardened) 822 64
Electroless Nickel (as plated) 542 50
Electroless Nickel (heat treated) 750 69
Mild Steel 164  

Nickel Silicon Carbide Technical Data

Material Composite matrix coating composed of high phosphate electroless nickel with 20-30% carbide in suspension
Application Electroless nickel plating (bath temperature 160oF)
Thickness .0005" - .002" uniform within .0001" - .0002"
Wear Resistance Excellent. Taber Wear Test 16.5 cubic mils/hour vs. hardened tool steel (62Rc) at 151.1 cu mils hour
Hardness 3,300 Knoop (hard Chrome at 70Rc=972 Knoop)
Substrates All aluminum series, carbon steel, tool steel, stainless, brass, and several engineered plastics
Surface Finish Polish up to a #3 diamond