On the fatigue strength of uncoated and DLC coated 7075-T6 aluminum alloy. (August 2019)

• Record Type: Journal Article
• Authors: Baragetti, S.; Borzini, E.; Božic, Ž.; Arcieri, E.V.
• Is Part Of: Engineering failure analysis. Volume 102(2019)
• Page Start: 219
• Page End: 225
• Publication Date: 2019-08
• Subjects: Light alloys -- 7075-T6 -- Rotating bending fatigue -- PVD -- DLC; UTS ultimate tensile strength (MPa) -- YS yield stress (MPa) -- N number of cycles -- σmax fatigue limit at N cycles (MPa) -- σfinal maximum nominal stress during the load block in which the rupture occurs (MPa) -- σprior maximum nominal stress at the previous load block (MPa) -- Nf number of cycles at which failure occurs during the last load block -- S stress to failure (MPa); System failures (Engineering) -- Periodicals; Fracture mechanics -- Periodicals; Reliability (Engineering) -- Periodicals; Pannes -- Périodiques; Rupture, Mécanique de la -- Périodiques; Fiabilité -- Périodiques; Fracture mechanics; Reliability (Engineering); System failures (Engineering); Periodicals; Electronic journals; 620.112
• DOI: 10.1016/j.engfailanal.2019.04.035
• Languages: English
• ISSNs: 1350-6307

Abstract

Abstract: 7075-T6 aluminum alloy is widespread in aerospace and automotive applications thanks to its favorable strength-to-mass ratio. However, the mechanical properties of the alloy decrease when it is exposed to aggressive media and cyclic loading. The deposition of low temperature hard coatings such as Diamond-Like Carbon (DLC) Physical Vapor Deposition (PVD) coatings guarantees good tribological behavior and corrosion resistance without compromising the mechanical properties of the substrate. The influence of DLC PVD coating deposition on the fatigue strength of the alloy in air environment is here described. Highlights: The effects of the DLC PVD coating deposition on 7075-T6 fatigue strength was investigated. For a number of cycles in the range 2e5-1e7, DLC coating deposition gives a reduction of the fatigue strength. The traces of polishing can be the origin of crack nucleation.