Delamination of layered materials under impact loading

Dinç, Dinçer
In this study, a cold worked tool steel and a low carbon steel ( St 37 ), which were joined by brazing, were subjected to impact and shear loading. The end product is used as paper cutting blades in the industry. Effects of different brazing filler metals on the delamination of the blades under impact loading and on the impact toughness of the blades were studied. The target is to achieve higher impact toughness values without delamination. Impact toughness of the steels, joined by Cu, CuNi and BNi brazing filler metals and separation of brazed surfaces under shear loading were studied. The microstructures that were formed as a result of each application were studied by scanning electron microscopy and x-ray diffraction. The results indicate that brittle intermetallic compounds are formed in BNi brazing filler metal application. It is observed that CuNi alloy with 24% wt Ni form stronger bonds with the base metals than pure Cu and 10% wt Ni CuNi alloy.


Dynamic strain aging of dual phase steels in forming applications
Bayramin, Berkay; Efe, Mert; Department of Metallurgical and Materials Engineering (2017)
Sheet metals are subjected to certain temperatures (25-200oC) and strain rates (1-10 s-1) during forming applications. These thermomechanical conditions may cause dynamic strain aging (DSA) in various grades of steels including dual phase (DP) steels. DSA represent itself as serrations in the stress-strain curves. Two grades of DP steels (DP590 and DP800) were studied systematically at different strain rates (10-3s-1-1s-1) and temperatures (25oC-400oC) to investigate the DSA effects on the mechanical proper...
Thin section high cooling rate solidification, thermomechanical processing and characterization of AISI DC53 cold work tool steel
Çardaklı, İsmail Seçkin; Kalkanlı, Ali; Department of Metallurgical and Materials Engineering (2019)
In this study, firstly, the solidification behaviour of AISI DC53 cold work tool steel was investigated by means of a cooling curve and its first derivative. Copper and sand wedge-shaped moulds were used to obtain various solidification rates. To reveal the cooling rate degree during solidification, the secondary dendrite arm spacing of the steel alloy was examined by scanning electron microscopy (SEM). The solidification rates of each section for both wedge steel samples were calculated by means of the sec...
Earthquake performance of un-stiffened thin steel plate shear walls
Mörel, Osman Fuat; Yılmaz, Çetin; Department of Civil Engineering (2004)
In this study two dimensional steel frames, reinforced with un-stiffened thin steel panels, are investigated. In the first part of the study, the strip model, a method for analyzing un-stiffened thin steel plate shear walls, was investigated. Sensitivity studies to investigate the influence of the number of strip members to be used to in the strip model and their angle of inclination were conducted. In the second part, responses of various un-stiffened steel plate shear wall systems to lateral loads were in...
Non-destructive evaluation of residual stresses in the multi-pass steel weldments
Erian, Gökhan; Gür, Cemil Hakan; Batıgün, Caner; Department of Metallurgical and Materials Engineering (2012)
The purpose of this thesis is non-destructive determination of residual stress state in the multi-pass welded steel plates by Magnetic Barkhausen Noise (MBN) technique. To control the effectiveness of the developed procedure, continuous MBN measurements on the heat affected zone and parent metal of the welded plates were performed. In the experimental part, various steel plates were welded with different number of weld passes. Various series of samples were prepared for residual stress and for angular defle...
An Investigation of bainitic transformation in low carbon alloy and high carbon railway steels
Öztürk, Zeynep; Ögel, Bilgehan; Department of Metallurgical and Materials Engineering (2018)
In this thesis study, bainitic transformation in high carbon railway steel and boron steel was investigated. Bainitic structure known as having high strength and high toughness at the same time. Mechanical properties of bainite were compared with the tempered martensite phase which is commonly used phase in industry. R260 and 32CrB4 steels were used in this study. Different heat treatments were applied to these steels for bainitic transformation. Austenitization was done at 850°C for R260 steel and at 880°C...
Citation Formats
D. Dinç, “Delamination of layered materials under impact loading,” M.S. - Master of Science, Middle East Technical University, 2003.