An investigation on the fatigue behaviour of Al 7075-T6 coated with titanium nitride using physical vapour deposition process
- 作者：R.H. Oskouei ; reza.oskouei@monash.edu ; R.N. Ibrahim
- 关键词：A. Non-ferros metals and alloys ; B. Film and sheet ; E. Fatigue
- 刊名：Materials and Design
- 出版年：2012
- 期刊代码：56_02613069
- 类别：ms
- 出版时间：August, 2012
- 卷：39
- 期：Complete
- 页码：294-302
- 文件大小：3499 K
摘要
This paper investigates the fatigue behaviour of aluminium alloy 7075-T6 coated with 3-渭m-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.