Wet or Dry – Hardness, Stiffness and Wear Resistance of Biological Materials on the Micron Scale

The present paper reports on the influence of humidity on hardness and stiffness measurements of biological materials. For the first time abrasion tests on the micrometer‐scale were performed on human dentin and enamel and, moreover, on tools of non‐vertebrates. Hardness and modulus can depend strongly on the water content; large differences can appear between wet samples measured under fluid or in air.