Effect of spherodizing on machinability characteristics and microstructure of medium carbon steels

Yanardağ, Emre
This study includes examination of the machinability characteristics of two medium carbon steel types (SAE 1040 and SAE 1050) as a result of spherodizing treatment. Both steel types were handled into four categories according to their spherodizing treatment parameters (temperature and time). Microstructural investigation, hardness and ultrasonic sound velocity measurement (with both longitudinal and transverse waves) of these steels were performed, and effect of applied heat treatments on microstructure, hardness and ultrasonic sound velocity was investigated. Pulse-echo method has been used for ultrasonic sound velocity measurements, and measurements were performed with 5 and 10 MHz longitudinal and 5 MHz transverse wave probes. Tool life criterion was used for determining the machinability characteristics of the steels. For this purpose, flank wear land measurements were performed on the cutting tools. Results have showed that, by appliying heat treatment it is possible to change the microstructure, hardness, ultrasonic sound velocity and machinability characteristics of a steel.


Effect of Microstructure on the Mechanical Behavior of Reactive Magnetron Sputtered Al2O3/TiO2 Multilayer Ceramics
Dericioğlu, Arcan Fehmi (Japan Institute of Metals, 2008-11-01)
Mechanical characteristics of reactive magnetron sputtered Al2O3-TiO2 multilayer ceramics were studied. Tailored mechanical properties such as moderately high hardness and reasonable toughness were achieved through varying sputtering process parameters resulting in microstructural control at nano-scale. Interchanging Al2O3 and TiO2 layers with a single layer thickness of similar to 65-70 nm were deposited on single crystal alumina (sapphire) substrates to form the multilayer structure composed of 10 layers....
Effect of surface roughness in microchannels on heat transfer
Turgay, Metin Bilgehan; Güvenç Yazıcıoğlu, Almıla; Department of Mechanical Engineering (2008)
In this study, effect of surface roughness on convective heat transfer and fluid flow in two dimensional parallel plate microchannels is analyzed by numerically. For this purpose, single-phase, developing, laminar fluid flow at steady state and in the slip flow regime is considered. The continuity, momentum, and energy equations for Newtonian fluids are solved numerically for constant wall temperature boundary condition. Slip velocity and temperature jump at wall boundaries are imposed to observe the rarefa...
Effect of carbon nanotube surface treatment on the morphology, electrical, and mechanical properties of the microfiber-reinforced polyethylene/poly(ethylene terephthalate)/carbon nanotube composites
Yesil, Sertan; Bayram, Göknur (2013-01-15)
The aim of this study is to investigate the effects of carbon nanotube (CNT) chemical properties, CNT content, and molding temperature on the morphology, electrical, and mechanical properties of the microfiber-reinforced polymer composites. These composites were prepared by extrusion and hot stretching the poly(ethylene terephthalate) (PET)/CNT phase in high density polyethylene (HDPE) matrix. Surfaces of the CNT were modified by purification with strong acid mixture (HNO3 : H2SO4 mixture 1 : 1 by volume) f...
Computation of drag force on single and close-following vehicles
Örselli, Erdem; Çetinkaya, Tahsin Ali; Department of Mechanical Engineering (2006)
In this study, application of computational fluid dynamics to ground vehicle aerodynamics was investigated. Two types of vehicle models namely, Ahmed Body and MIRA Notchback Body and their scaled models were used. A commercial software "Fluent" was used and the effects of implementing different turbulence models with wall functions were observed. As a result, an appropriate turbulence model was selected to use in the study. The drag forces, surface pressure distributions and wake formations were investigate...
Process characterization of composite structures manufactured using resin impregnation techniques
Miskbay, Adem Onur; Parnas, Kemal Levend; Department of Mechanical Engineering (2009)
The aim of this study is to investigate and compare the properties of two layer carbon epoxy composite plates manufactured using various resin impregnation techniques; Resin Transfer Molding (RTM), Light RTM (LRTM), Vacuum Assisted RTM (VARTM) and Vacuum Packaging (VP). Throughout the study a different packaging method was developed and named Modified Vacuum Packaging (BP). The mechanical properties of composite plates manufactured are examined by tensile tests, compressive tests, in-plane shear tests and t...
Citation Formats
E. Yanardağ, “Effect of spherodizing on machinability characteristics and microstructure of medium carbon steels,” M.S. - Master of Science, Middle East Technical University, 2004.