Porous metal bearings are most commonly produced through which method?

The production of porous metal bearings is most commonly achieved through sintering. Sintering involves compacting metal powders under pressure and then heating them to a temperature below the melting point of the main constituent metal. This process allows the particles to bond together, creating a solid structure while maintaining porosity within the material.

The porosity in these bearings is essential as it allows for the retention of lubricating oil, reducing friction and wear during operation. Sintered bearings can also be tailored for specific properties, such as strength and permeability, making them ideal for various mechanical applications. The process is highly efficient and cost-effective, as it minimizes material waste and can produce complex shapes.

In contrast, drop forging involves shaping metal through plastic deformation using a hammer or die, which is not suitable for creating porous structures. Resin casting and compression moulding, typically used for polymers or composites, also do not align with the requirements for producing porous metal bearings. Therefore, sintering stands out as the most effective method for this specific purpose.