SEARCH RESULT

Year

Subject Area

Broadcast Area

Document Type

Language

2 results listed

2018 Investigation of low velocity impact response of multi-walled carbon nanotube added alumina/epoxy reinforced nanocomposites

The low-velocity impact response of Multi-Walled Carbon Nanotube (MWCNT) added alumina-epoxy nanocomposites is investigated. Alumina fiber reinforced nanocomposites which contain 0.1%, 0.3%, 0.5%, 0.7% and 1% per weight MWCNTs of epoxy resin are produced by using Vacuum Resin Transfer Molding (VARTM) method. Three levels of energy which are 20J, 25J and 30J are applied to nanocomposites. The time history response of load, displacement, velocity, and energy are measured and reported. In addition, the composite damage associated with each energy level is compared to different MWCNT per weight. The effect of MWCNTs was analysed on the fracture surface of composites through optical and scanning electron microscopy (SEM). Results demonstrated that MWCNTs improved impact response and limited the damage size of nanocomposites. The addition of 1% MWCNTs resulted in an increase in energy absorption.

International Symposium on Light Alloys and Composite Materials
UHAKS

Sezer Picak Ahmet AKDEMİR Ahmet Avcı Yusuf Usta

346 248
Subject Area: Chemistry Broadcast Area: International Type: Oral Paper Language: English
2018 The Role of Twinning in The Deformation of Single Crystalline High- And Medium Entropy Alloys

Tensile deformation response of Fe40Mn40Co10Cr10 high entropy alloy (HEA) and equiatomic NiCoCr medium entropy alloy (MEA) single crystals oriented along the [111] crystallographic orientation was investigated at room temperature. In-situ digital image correlation and transmission electron microscopy observations revealed that two micro- deformation mechanisms govern the strain hardening in the Fe40Mn40Co10Cr10 HEA, namely planar slip and twinning, while twinning dominates in the NiCoCr MEA. Consequently, the twin-slip interaction in the Fe40Mn40Co10Cr10 HEA leads to a higher rate of work hardening as compared to the NiCoCr MEA. However, NiCoCr MEA single crystals attain higher fracture strains and exhibit higher ultimate strength as compared to the Fe40Mn40Co10Cr10. HEA. The micro- deformation mechanisms responsible for these observations were investigated with detailed transmission electron microscopy analysis, which revealed that nanotwin formation within primary twins was prevalent at the early stages of deformation in NiCoCr MEA, significantly enhancing the ductility, while the higher strength levels are associated with the high volume fraction of twins with relatively small thickness.

International Symposium on Light Alloys and Composite Materials
UHAKS

Sezer Picak B.Uzer J. Liu D. Canadinc Y.I. Chumlyakov I. Karaman

388 231
Subject Area: Chemistry Broadcast Area: International Type: Oral Paper Language: English