Uniaxial plain fatigue and fretting fatigue tests were carried out on detonation gun sprayed Cu-Ni-In coating on Al-Mg-Si alloy samples. The samples in three conditions were considered: uncoated, as-coated and ground after coating. Ground coated specimens exhibited superior plain fatigue and fretting fatigue lives compared with uncoated and as-coated specimens. The life enhancement has been discussed in terms of surface finish and residual compressive stresses at the surface. © 2008 Elsevier Ltd. All rights reserved.

Sundararajan G

Department of Metallurgical and Materials Engineering

S. Ganesh Sundara Raman

Alloys

Aluminum

Cerium alloys

Coatings

Copper

Detonation

ELECTRON GUNS

Fatigue of materials

Fatigue testing

FRETTING CORROSION

GRINDING (COMMINUTION)

Grinding (machining)

Nickel

Pesticides

Residual stresses

Silicon

Silicon alloys

Strength of materials

AL-MG-SI ALLOY

CU-NI-IN

DETONATION SPRAY COATING

FRETTING FATIGUE

Grinding

Copper alloys

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

International Journal of Fatigue

Detonation gun spray technique was employed to coat Al-Mg-Si alloy (AA 6063) specimens with Cu-Ni-In powder. Coated samples were characterized with reference to the microstructure, porosity, residual stresses, microhardness and surface roughness. Plain fatigue (without fretting) and fretting fatigue tests were carried out at room temperature on uncoated and coated specimens. The detonation gun spray process resulted in a dense coating of almost uniform deposition with low porosity (0.3%) and good adhesion between the substrate and the coating. Under plain fatigue loading 40&nbsp;μm thick coated samples exhibited superior lives compared with uncoated and 100&nbsp;μm thick coated specimens due to the presence of higher surface compressive residual stress in the former. Delamination-induced failure resulted in inferior lives of 100&nbsp;μm thick coated specimens. Under fretting fatigue deformation 40&nbsp;μm thick coated specimens exhibited superior lives compared with 100&nbsp;μm thick coated samples owing to higher compressive residual stress at the surface and better interfacial adhesion. At 120&nbsp;MPa stress level 40&nbsp;μm thick coated specimens exhibited superior fretting fatigue life compared with uncoated sample and at stress levels above 120&nbsp;MPa the converse was true. This was attributed to interface cracking at higher stress levels. © 2006 Elsevier B.V. All rights reserved.

Surface and Coatings Technology

Effect of detonation gun sprayed Cu-Ni-In coating on plain fatigue and fretting fatigue behaviour of Al-Mg-Si alloy

The present work describes the effect of shot blasting on plain fatigue (without fretting) and fretting fatigue behaviour of Al-Mg-Si alloy AA6061. Shot blasting significantly increased the plain fatigue life by a factor 2.8 and fretting fatigue life by a factor 2.4 at a maximum cyclic stress (σmax) of 169 MPa, but at higher stress levels shot blasting slightly reduced both the plain fatigue and the fretting fatigue lives. At a maximum cyclic stress of 169 MPa, the stabilized value of coefficient of friction in the shot blasted condition was lower than that in the T6 condition (0.55 against 0.60), but at a maximum cyclic stress of 265 MPa, it was around 0.82 in the T6 condition and 0.84 in the shot blasted condition. © 2004 Elsevier Ltd. All rights reserved.

Effect of shot blasting on plain fatigue and fretting fatigue behaviour of Al-Mg-Si alloy AA6061

Effect of grinding on plain fatigue and fretting fatigue behaviour of detonation gun sprayed Cu-Ni-In coating on Al-Mg-Si alloy

Journal	International Journal of Fatigue
ISSN	01421123
Open Access	No