ANS:B - self lubricating bearing and cemented carbide.

Powder metallurgy processing can be used for making self-lubricating bearings and cemented carbide. Powder metallurgy is a manufacturing process that involves forming metal powders into desired shapes and then consolidating them through sintering, forging, or other techniques. It offers several advantages, including the ability to produce complex shapes, high precision, and the incorporation of alloying elements or additives to enhance properties. Self-lubricating bearings can be produced using powder metallurgy by incorporating solid lubricant particles, such as graphite or molybdenum disulfide, into the metal matrix during the powder mixing stage. This results in bearings with inherent lubrication properties, reducing friction and wear during operation. Cemented carbide, which is a composite material consisting of hard carbide particles (such as tungsten carbide) embedded in a metal matrix (usually cobalt), can also be manufactured using powder metallurgy. The process involves mixing fine carbide powders with a binder (such as cobalt) and then compacting and sintering the mixture to form dense, hard, and wear-resistant carbide tools and components. While powder metallurgy can be used for producing various other components, including connecting rods and pistons, the specific examples of self-lubricating bearings and cemented carbide are particularly notable for their widespread use and importance in various industrial applications.