The two numbers that matter
Coating adhesion is better described as a function of two parameters together: peak height (H) and peak density (Pd) — expressed simply as A = f(H, Pd). Peak height tells you how tall the anchor points on a profiled surface are. Peak density tells you how many of them there are per unit area. A surface can have an impressively high peak height and still bond poorly if those peaks are sparse and irregular; conversely, a lower, denser, more uniform profile can out-perform a taller but patchy one. Profiled surfaces are, by nature, irregular: peak height, sharpness and surface area cannot be fully captured by a single reported value.
Why this matters for spec writers and inspectors
Two coatings bonded to two surfaces with identical average peak height can have very different in-service lifetimes if their peak density differs. For liquid-applied coatings, both a high-H/low-Pd surface and a low-H/high-Pd surface can, in principle, achieve an adequate bond — which is exactly why industry standards specify a target range and a repeatable, measurable process, rather than a single height reading taken in isolation.
What this means in practice
A repeatable mechanical process — rather than a manually variable one — is what keeps peak density consistent from pass to pass, not just peak height. That consistency is the entire premise of MontiPower®'s Controlled Preparation System: the same accelerator-bar mechanism produces the same profile characteristics every time, on every operator's shift. For the field-measurement side of this — how inspectors actually verify peak height and profile consistency on site — see our anchor profile measurement field guide.
