Practical adhesion of organic coatings to metals: The role of the interphase and its residual stresses

The laminated composite material is made of ply which are specically used in automotive, aerospace and military applications due to less in weight and high strength to weight ratio. The role of structural strength is very important in composites, as the material is weak in inherent strength leads to damage of equipment made with the laminated composite. Hence, an accurate understanding of their structural geometrical behavior for residual stresses is required, such as residual stresses with different aspect ratios. In present work, various aspect ratios of laminated composite and its residual stresses are investigated using finite element analysis. The numerical results showed, on the residual stresses, that the effects the change the residual stresses due change of aspect ratio of laminated Graphite/epoxy composite.

Download Full-text

Lifetime Assessment of Particulate Ceramic Composite with Residual Stresses

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.754.107 ◽

2017 ◽

Vol 754 ◽

pp. 107-110

Author(s):

Luboš Náhlík ◽

Zdeněk Majer ◽

Kateřina Štegnerová ◽

Pavel Hutař

Keyword(s):

Residual Stresses ◽

Crack Propagation ◽

Mechanical Loading ◽

Ceramic Composite ◽

Subcritical Crack Growth ◽

Particulate Composites ◽

Time To Failure ◽

Complex Load ◽

Composite Surface

A micro-crack propagation in particulate ceramic based composite was studied using finite element method (FEM). Subcritical crack growth (SCG) was numerically simulated under complex load conditions (mechanical loading and loading by internal residual stresses). The effect of residual stresses on the crack propagation was studied. Two-dimensional computational model of particulate ceramic composite with material properties corresponding to low temperature co-fired ceramics (LTCC) was developed. The results indicate that the presence of residual stresses significantly reduces values of stress intensity factor in the vicinity of composite surface and the direction of residual stresses around the particles contributes to the micro-crack deflection from the particles. The time to failure of the composite under mechanical loading was determined. Results obtained contribute to a better understanding of the role of residual stresses during micro-crack propagation in ceramic particulate composites.

Download Full-text

Viscoplastic Buckling of Silicon Ribbon

Journal of Applied Mechanics ◽

10.1115/1.3173070 ◽

1987 ◽

Vol 54 (3) ◽

pp. 563-570 ◽

Cited By ~ 3

Author(s):

C. T. Tsai ◽

O. W. Dillon

Keyword(s):

Residual Stresses ◽

Response Function ◽

Growth Direction ◽

Viscoplastic Material ◽

Material Response ◽

Lateral Deflection ◽

Buckling Behavior ◽

Silicon Ribbon ◽

Creep Buckling

Silicon ribbon grown by the dendritic web process passes through a rapidly changing thermal profile in the growth direction. This rapidly changing profile induces stresses which cause buckling. Based on a viscoplastic material response function (Haasen-Sumino model), the creep buckling behavior of the silicon ribbon is investigated. The lateral deflection speeds describing the viscoplastic buckling behavior are calculated. It is found that the deflections of some modes increase with time while others die out. The role of the residual stresses in viscoplastic buckling is examined.

Download Full-text