Engineering Materials | An Overview On Metal Part Finishes
Finishing for Engineered Parts
Most parts will require some form of finish to protect them from the environment or to improve the appearance or performance of the part in service. The type of finish best suited to the part depends on what the part is made from. The most common finishes for parts and components include plating, galvanising, painting, and dipping.
Here is a brief rundown of the general types of finishes applied to engineered parts and components used across a wide range of industries.
Most Common Types Of Part Finishes
Plating
This involves using a process called electrolysis to electrically plate a different material onto the surface of a part. It normally involves putting a very thin layer of an expensive material over a lower-cost material mostly to improve appearance but this is not always the case. Engineered parts, can be plated with a low-cost material like zinc to prevent rusting for indoor applications. For very high-end parts that require very special properties, these parts can be plated in gold or silver depending on the application.
Plating is very similar to a process called anodising which is used to put a protective layer on finished parts. Anodised parts are normally aluminium and are an electrochemical process using electricity. Anodised parts can be hard or soft anodised and can be done in many different colours.
Hot Dip Galvanising
This is normally done on steel parts and involves dipping the parts into a bath of molten zinc so that the external surfaces get covers in zinc. There is normal dipping and for general parts but threaded items are spin dipped which involves putting the dipped parts into a spinning basket immediately after dipping to centrifugally remove excess material from the surface so that the threaded section is clean and smooth. In order for the process to be 100% successful the part need to be completely clean before dipping.
Painting
This can be a wet or dry/powder process whereby many different chemical paints are applied to the surface of the parts. Normally done on parts that are used indoors but high spec paint finishes are applied to outdoor items like cars. Paints and painting is a complete industry of its own and is very much part-specific depending on the application.
Dipping
This involves dipping the parts into an oil or chemical solution to prevent rusting of the parts or corrosion. Normally a temporary process to protect parts in transit or between locations.
Sand Blasting
This is whereby sand is used in a high-speed airflow to blast away or clean the surface of parts. Basically taking the surface down to the base metal. The process is manual and is extremely aggressive.
Shot Blasting
Steel Shot Abrasive
This is whereby shot or steel balls are used in a high-speed airflow to blast away or clean the surface of parts. Basically taking the surface down to the base metal. The process is manual and is extremely aggressive. Both processes are carried out in a controlled environment ideally in a sealed cabinet or if not possible the operator is wearing protective clothing with breathing apparatus.
Precision parts with a wide array of finishes
Donlouco Ireland has the capabilities, specifically CNC Machining, to manufacture a wide range of engineered parts with many different finishing requirements.
Donlouco is fully ISO 9001 and EN 1090 approved for CE marking. All parts and components including are manufactured to the highest possible standards and to exact customer requirements.
Precision parts use a wide array of manufacturing processes and finishes. CNC Machining, Forgings, Stamped, Punched, and Deep Drawn Parts with the required finish for maximum customer satisfaction.