Hard and Exotic Materials have grown in popularity as materials selected for high wear, high corrosion and high temperature environments.
What is Inconel?
Inconel is family of super alloys whose makeup all consistent of Austenitic Nickel and Chromium. The most popular grades of Inconel include 625 which is primarily selected for its corrosion resistance against a variety of sources, and 718 which is often used for its hardness and operating temperature range. Inconel is often used in applications such as turbine blades, heat exchangers, flanges and gaskets.
Why Plate Inconel?
Despite its superior wear resistance, Inconel like all metals can still be damaged and the cost of replacement is higher due to Inconel Alloys being more expensive to procure and machine. One option for the repair of worn Inconel components is to plate them.
The most common choice for this is Hard Chrome Plating. The hard and dense nature of the Chromium deposit compliments the attributes of the Inconel’s attributes and can be selectively plated to build up. The process of plating on Inconel and other super alloys is not so straight forward though and even with the correct preparation, many platers will encounter adhesion issues. The other problems with Hard Chrome as a process is that even though it can be built up, the more it is done so the less stable the deposit becomes, and as it relies on Hexavalent Chromium is not a ROHS compliant.
The other option used to coat Inconel is Electroless Nickel. This is an auto-catalytic process which has the advantage of producing an even deposit on uneven surfaces. This process would not necessarily be suitable for repair of worn parts but could add an extra layer of protection perhaps on more intricate components with thin walls.
A more natural way in which to repair or protect Inconel Components would be through Thermal Spray. B&B are able to take powdered materials which closely match the attributes of alloys such as 625 and 718, and spray them on at high velocities and temperatures so they form a strong bond with the base material. This is an additive process that can be built up to be very thick without losing its composition, making it ideal for repairing Inconel Alloy components.
Plating With Inconel?
It is not possible to electro-plate using Inconel due to the complex nature of the different elements within the alloy. That means if you are looking to plate Inconel you would need to use a Thermal Spray process. This process can greatly extend part life and may be specified where Electroless Nickel cannot meet the requirements of Wear Resistance.
B&B are based just off the M1 near Huddersfield and are a fully ISO sub-contract manufacturer able to both machine and coat using Inconel Alloys.