What is the primary purpose of adding additives to metals?

The primary purpose of adding additives to metals is to improve properties. Additives can enhance various characteristics of metals, such as their strength, hardness, corrosion resistance, or ductility. By carefully selecting and incorporating specific additives, manufacturers can tailor the metal to meet the desired performance criteria for particular applications. For example, adding elements like chromium can enhance corrosion resistance in stainless steels, while carbon can increase hardness in steel alloys.

The other options do not align with the typical objectives of using additives. Increasing weight does not generally serve any beneficial purpose in metal formulation, as most applications favor lightweight materials for efficiency. Decreasing durability would be counterproductive, as enhancements through additives are aimed at improving the lifespan and performance of metals, not diminishing them. Altering color is not the primary aim of additives, as the primary focus is usually on enhancing physical and mechanical properties rather than aesthetic qualities.