What metal removal variable has the greatest effect on tool life?

Cutting speed, often expressed as surface feet per minute (SFM), has a significant impact on tool life in machining processes such as milling. As cutting speed increases, the temperature at the tool's cutting edge rises due to friction and the shear forces involved in the cutting process. Higher temperatures can accelerate tool wear and reduce the life of the cutting tool, causing it to become dull more quickly.

An optimal cutting speed is critical to achieving the best performance; if the speed is too low, material removal rates may be inefficient, resulting in extended machining times. Conversely, if the speed is too high, it can lead to rapid tool degradation. Tool manufacturers often provide recommendations for cutting speeds based on the material being machined and the tool type, which are essential to ensure a balance between productivity and tool longevity.

Although other variables such as depth of cut, feed rate, and lubrication also influence tool life, they tend to have a less pronounced effect on wear compared to cutting speed. For instance, while increasing the depth of cut or feed rate can enhance material removal, these changes may not dramatically affect the temperature and wear characteristics of the tool as cutting speed does. Additionally, proper lubrication can help reduce friction and heat, but it cannot alleviate the fundamental effects of