Materials Technology - Surface Treatments and Coatings

Surface Treatment

Modifying a part's surface to enhance properties like appearance, corrosion resistance, hardness, fatigue life, and wear resistance.

Coating

Depositing a different material onto the original material.

Surface Cleaning Methods

Mechanical (abrasive blasting, ultrasonic cleaning) and chemical (alkaline, acid, solvent, emulsion cleaning).

Surface Treatment Goal for Steels

Achieve high surface hardness with a tough core.

Nitriding

Nitrogen surface adsorption to improve mechanical properties such as high hardness and corrosion resistance.

Carburizing

Increases surface hardening by adding ~1% C to the surface of low carbon steels (0.08-0.25% C).

Galvanization

Active metallic coatings (anodic) relative to steel, providing sacrificial protection.

Electrodeposition

Electrochemical coating via metallic ion deposition on a cathode.

Thermal Spraying

Coating materials (metals, carbides, ceramics) applied melted or partially melted to provide corrosion, wear, and high-temperature oxidation resistance.