The Rz value is a measurement used to assess the surface roughness of materials. It represents the average vertical distance between the highest peaks and the lowest valleys on a surface over a specified sampling length. This value helps engineers and manufacturers determine how smooth or rough a surface is, which can affect the performance and durability of a product. In manufacturing, a lower Rz value indicates a smoother surface, which is often desirable for components that require precise fitting or reduced friction. Conversely, a higher Rz value may be acceptable for surfaces that need better grip or adhesion. Understanding the Rz value is crucial for quality control in various industries.