Which term describes the preparation applied to metal surfaces to keep them free of oxides?

• A. Eutectic wax.
• B. Flux.
• C. Wiping action.
• D. Capillary action.

Answer: (B)

Flux is a material that is used in metalworking processes, particularly in soldering and welding, to prevent the formation of oxides on metal surfaces. When metals are heated, they can react with oxygen in the air, forming an oxide layer that can hinder bonding or soldering. Flux serves to facilitate the flow of molten filler material and to protect the metal surfaces by lowering the melting point of any oxides that may form, allowing them to be removed or minimized during the heating process.

In addition to enhancing the bonding process, flux also helps improve the wetting characteristics of the filler material, ensuring a strong connection between the metal parts being joined. This is crucial for achieving a high-quality weld or solder joint, as any interference from oxides can severely compromise the integrity of the joint.

The other terms, such as eutectic wax, wiping action, and capillary action, do not specifically refer to the process of keeping metal surfaces free of oxides in the same direct manner that flux does. Eutectic wax is more related to low-temperature melting alloys, wiping action refers to the physical process of spreading or cleaning, and capillary action pertains to the movement of liquids in narrow spaces, which, while related to fluid dynamics, does not