Coating for advanced engineering applications – including the aerospace and semiconductor industries.

Hardide-W has been developed for advanced engineering applications which will benefit from the coating’s chemical and corrosion resistance, ductility, extremely high melting temperature, strong adhesion and non-porous structure, but which do not require high hardness and wear resistance. Hardide-W consists of high purity metal tungsten with small amounts of special alloying elements which enhance the material’s mechanical properties. It is a REACH-compliant replacement for cadmium plating.

Hardide-W properties include:

– The coating technology achieves high deposition rates and low residual stresses enabling the production of thick coatings in excess of 100 microns and is also suitable for producing very thin conformal coatings of a few microns thickness. This expands the range of applications covering a wide variety of coating thicknesses.

– Can be applied to internal and external surfaces and complex shapes uniformly

– Pore-free coating has enhanced chemical resistance and is an excellent barrier against corrosion

– Can be applied to a wide range of metals including various grades of stainless steel, tool and alloy steels, nickel, copper and cobalt-based alloys

Hardide Coatings’ UK and USA manufacturing sites are approved to ISO 9001 and aerospace AS 9100 certification. The UK site is also accredited to Nadcap and ISO 14001.

Examples of Hardide-W applications include:

– A corrosion barrier coating with enhanced anti-galling properties replacing toxic cadmium plating on aircraft components

– Coating on anodes which generate X-rays while dissipating the heat and ensuring excellent electrical conductivity even in thermal shock and thermal cycling conditions

– Coating on graphite components and tooling for high temperature vacuum reactors used in semiconductor manufacturing

KEY PROPERTIES

PARAMETER HARDIDE-W
Microhardness [kgf/mm2] 400 – 500 Hv
Coating Thickness Ranging from 5 to 100 microns (0.0002 – 0.004”)

Thicker or thinner coatings can be produced, ask for details.

Coating Toughness Excellent. Good resistance to thermal shock.
Strain to Fracture Higher than 0.3% (3000 microstrain)
Adhesion Tensile Bond Strength Better than 70 MPa or 10,000 psi

Under standard bond test ASTM C633-01, the Hardide coating adhesion bond has been proven to be higher than the adhesive ultimate strength of 70 MPa (10,000 psi)

Coating Composition Metal tungsten with small amounts of alloying elements

Does not contain Cobalt or other metal binder materials used in Cemented Carbides and thermal spray coatings

Coating Porosity < 0.5% as measured in accordance with ASTM E2109
Appearance Coating as applied is light gray

Finishes to a high metallic lustre when polished

Finishing Operations Grinding, Honing, Lapping, Polishing, Super-finishing
Surface finish As coated 0.4 – 0.6 microns Ra / 16-24 μin

Can be polished to 0.2 – 0.3 microns Ra / 8 – 12 μin

Can be super-finished to 0.02 microns Ra / 0.8 μin

Corrosion Resistance Resistant to acids, H2S and some aggressive chemicals
Coating Temperature Typically up to 500°C / 932°F max

Optional 480°C / 896°F max for temperature sensitive substrates

Electrical Resistivity @ 20°C 5.5 microhm-cm
Linear Coefficient of Expansion 4.3 x 10-6 per ºC
Density @ 20ºC 19.3 (gm/cc)
Thermal Conductivity @ 20ºC 174 W/m·K
Specific Heat Capacity @ 20ºC 0.132 J/g·K