Mining environments are both very corrosive and abrasive. Mine waters are typically acidic and can cause high rates of attack of unprotected steel. In addition, the dust produced during mining can result in severe erosion.
The electroless nickel plating process provides coatingss which withstand these conditions with little attack. Common applications are hydraulic components, framing, cylinder heads for jetting pumps, pipeline connections and tubing, and mine engine components.
- Corrosion protection
- Optical properties (i.e. low or high reflectivity)
In most cases combinations are used to qualify electroless nickel coatings for military and defense.
MOLDS & DIES
The ability of electroless plating to provide a uniform deposit, even into deep recesses, helps to ensure that the finish on a mold will duplicate the original surface. The natural lubricity of the coating provides smooth flow during injection and quick and easy release of the part. Because of its high hardness at elevated temperatures, the electroless nickel coating minimizes erosion and abrasion of molds and dies and helps to extend their lives.
The coating also provides excellent protection against the corrosive fumes produced during molding such plastics as ABS, PVC, polycarbonate, acrylics and materials with thermoplastic additives. Similarly, electroless nickel plating has been found to provide a superior coating for zinc diecast dies and glass molds.
PRINTING & TEXTILE
The use of electroless nickel plating for cylinders and rolls used in the printing and textile industries has grown greatly during the past several years. The ability of the coating to deposit uniformly allows the cylinder to be machined to size, balanced and plated without subsequent finishing or grinding.
Typical plating thicknesses are 25 to 50 μm (1 to 2 mils). The life of this equipment is also greatly extended by this lubricious and wear resistant coating.
Other common textile applications include thread guides, fiber feeds, fabric knives, heddles, bobbins, shuttles, rapiers, ratchets, knitting needles and picks.
For decades tanks containing corrosive media are plated with these corrosion resistant coatings. Another example are diesel engine shafts which benefit from the nickel coatings exceptional wear resistance and fretting characteristics.
In addition there are many more applications like unloading connections, trunions, bolts, etc.
WOOD & PAPER
Wood handling and pulp and paper equipment operate under conditions of severe corrosion and abrasion. The salt and organic acids present in woods can cause high rates of attack on common materials.
The electroless nickel plating process provides coatings with good protection against these conditions and are presently being used for knife holder cover plates and for abrading plates for wood cutting and chopping machines. Differential pins are also a large application area.