The penetration behavior of repeated hemisphere core sandwich structures: An experimental and numerical study
Turan, Ali Kıvanç, author.

The penetration behavior of repeated hemisphere core sandwich structures: An experimental and numerical study

Turan, Ali Kıvanç, author.

Yazar Ek Girişi
Turan, Ali Kıvanç, author.

Fiziksel Tanımlama
xv, 114 leaves: illustrarions, charts;+ 1 computer laser optical disc.

In this study, penetration behavior of novel core structure consisting hemispherical and cylindrical parts was investigated. Core units were manufactured with deep drawing method in two thicknesses to have monolithic form without any sort of assembly method or element. Produced specimens were then subjected to penetration tests at low and intermediate velocities against blunt, conical and hemispherical tipped indenters using special fixtures and apparatuses on conventional testing equipment. Effect of heat treatment on penetration behavior was investigated to observe whether residual stresses arise from manufacturing process changes the penetration behavior. Confinement effects were studied experimentally with a special fixture, allowing tested specimen to be radially confined with other core units as in an armor structure. Finally, experimental work was finished by conducting a case study where core units were subjected to spherical projectile impact up to impact velocities of 180 m.s-1 in a composite sandwich structure. Results show that each indenter geometry showed unique deformation characteristics in testing of both core units and both of the core geometries were able to hold a steel spherical projectile with mass of 110 g without full perforation at impact velocity of 180 m.s-1. Details of experimental results were presented in each chapter. Study also included modeling parts where core units were numerically produced with residual stresses and strains and good correlation was noted where thickness was compared with actual measurements on core units. Test conducted on single core structure in as-received and heat-treated condition were also repeated in numerical environment, where numerical study exhibited good correlation on both forcedisplacement curves and deformation of core units with tests. Correlation achieved with experimental study has led into further investigations of strain rate and micro-inertia where behavior of core units was studied at numerical impact velocities of 300 m.s-1. Results show that both strain rate and micro-inertia increase the local maximums and average of force levels. Effect of strain rate and micro-inertia is clearly distinguished for a threshold displacement level where micro-inertia is further dominant on behavior.

Konu Başlığı
Penetration mechanics.
Glass fibers.
Composite materials.
Finite element method.
Sandwich construction.

Yazar Ek Girişi
Taşdemirci, Alper,

Tüzel Kişi Ek Girişi
İzmir Institute of Technology. Mechanical Engineering.

Tek Biçim Eser Adı
Thesis (Doctoral)--İzmir Institute of Technology:Mechanical Engineering.
İzmir Institute of Technology: Mechanical Engineering--Thesis (Doctoral).

Elektronik Erişim
Access to Electronic Versiyon.

LibraryMateryal TürüDemirbaş NumarasıYer NumarasıDurumu/İade Tarihi
IYTE LibraryTezT001744TA492.S25 T92 2018Tez Koleksiyonu