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Mémoires de Mathématique et de Physique, tirés des registres de l'Académie Royale des Sciences de l'année 1760, pages 1-45; Note du transcripteur: Cette transcription se veut parfaitement fidèle à l'original du mémoire (accessible sur le site Gallica de la BNF), ma motivation étant avant tout de rendre celui-ci plus facile d'accès et de lecture, et rendre ainsi hommage à cette oeuvre pionnière, et relativement méconnue parmi toutes les contributions de Daniel Bernoulli. Je me suis donc contenté d'appliquer des modifications mineures liées à l'orthographe moderne, sans changer la ponctuation (qui, quoiqu'un peu datée, ne suscite pas de difficulté de lecture), la grammaire étant par ailleurs parfaitement conforme aux règles encore en usage. Il va de soi que tous les retours sont les bienvenus sur cette transcription, qui pourra faire l'objet de révisions futures en fonction de ceux-ci.

Friction and wear minimizing coatings are crucial for applications in combustion engines and medical implants. Their performance is typically limited by mechanical failure especially due to local overload. In this work, the contact damage creation, evolution, and final morphology of hydrogenated diamond-like carbon (DLC)-coated titanium (Ti) substrates are investigated. The influence of the DLC film thickness and the elastic–plastic deformation of the Ti on the contact damage are studied by microindentation and static finite-element analysis. Film thickness, indenter radius, and applied load as well as the elastic–plastic deformation of the Ti are shown to significantly affect contact damage. A failure plot is presented with the location of first failure in the DLC and compared to the experimental observation. In addition, a case study with variable fracture toughness of the DLC and its influence on the failure plot is shown. The stress distribution in the DLC follows a transition from a membrane-like to a plate-like deformation behavior upon increasing the DLC film thickness. Thin DLC films reveal increased cracking in the inner zone of the indent, while thicker DLC films reveal pronounced edge cracking. These edge cracks were correlated to pop-ins in force–displacement curves upon microindentation. Finally, a film thickness optimization process is presented for hard and brittle films on soft and ductile metallic substrates., Journal of Materials Science, 50 (7), ISSN:0022-2461, ISSN:1573-4803