کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
830675 | 1470358 | 2012 | 9 صفحه PDF | دانلود رایگان |
This paper investigates the fatigue behaviour of aluminium alloy 7075-T6 coated with 3-μm-thick titanium nitride (TiN) coatings using a physical vapour deposition (PVD) process. Preliminary work demonstrated that the high operating temperature of the deposition process markedly reduced the tensile properties of the coating-substrate system by comparison to the uncoated Al 7075-T6. The low tensile properties of the coated material caused a considerable reduction in the load-carrying capacity under fatigue loading. Consequently, a substantial decrease of 90% was found in the fatigue life of the coated material. The lost tensile properties were then satisfactorily recovered by applying a post heat treatment to the coated alloy leading to significant fatigue life improvements to approach original properties of the uncoated Al 7075-T6. The evaluation of fatigue fracture surfaces at high magnifications indicated that the fatigue cracks initiated at the outer surface of the aluminium substrate under the coating thin layer.
► Decrease in the fatigue strength of Al 7075-T6 coated with TiN using a PVD process.
► Improvement in the fatigue strength of the coated alloy after re-applying T6 cycle.
► Reduced cyclic load-carrying capacity of the coated alloy was regained after T6 cycle.
Journal: Materials & Design - Volume 39, August 2012, Pages 294–302