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Full-Text Articles in Engineering

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel Nov 2011

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel

A.S. Md Abdul Haseeb

Biodiesel is currently in regular use as an alternative fuel over conventional petroleum diesel. However, corrosion of automotive materials is one of the concerns related to biodiesel compatibility issues. In addition, auto-oxidation of biodiesel can also enhance the corrosiveness of biodiesel. The present study aims to investigate inhibition effect of ethylenediamine (EDA), n-butylamine (nBA), tert-butylamine (TBA) against corrosion of cast iron. Static immersion tests in biodiesel in the presence (100 ppm) and absence of different corrosion inhibitors were carried out at room temperature for 1200 hours. At the end of the test, corrosion characteristic was investigated by weight loss measurements …


Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel Nov 2011

Effect Of Different Corrosion Inhibitors On The Corrosion Of Cast Iron In Palm Biodiesel

A.S. Md Abdul Haseeb

Biodiesel is currently in regular use as an alternative fuel over conventional petroleum diesel. However, corrosion of automotive materials is one of the concerns related to biodiesel compatibility issues. In addition, auto-oxidation of biodiesel can also enhance the corrosiveness of biodiesel. The present study aims to investigate inhibition effect of ethylenediamine (EDA), n-butylamine (nBA), tert-butylamine (TBA) against corrosion of cast iron. Static immersion tests in biodiesel in the presence (100 ppm) and absence of different corrosion inhibitors were carried out at room temperature for 1200 hours. At the end of the test, corrosion characteristic was investigated by weight loss measurements …


Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet R. Dokmeci, Kai-Tak Wan Jun 2011

Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet R. Dokmeci, Kai-Tak Wan

Kai-tak Wan

We report a technique to characterize adhesion of monolayered/multilayered graphene sheets on silicon wafer. Nanoparticles trapped at graphene-silicon interface act as point wedges to support axisymmetric blisters. Local adhesion strength is found by measuring the particle height and blister radius using a scanning electron microscope. Adhesion energy of the typical graphene-silicon interface is measured to be 151±28 mJ/m2. The proposed method and our measurements provide insights in fabrication and reliability of microelectromechanical/nanoelectromechanical systems.


Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan Jun 2011

Direct Measurement Of Graphene Adhesion On Silicon Surface By Intercalation Of Nanoparticles, Zong Zong, Chia-Ling Chen, Mehmet Dokmeci, Kai-Tak Wan

Mehmet R. Dokmeci

We report a technique to characterize adhesion of monolayered/multilayered graphene sheets on silicon wafer. Nanoparticles trapped at graphene-silicon interface act as point wedges to support axisymmetric blisters. Local adhesion strength is found by measuring the particle height and blister radius using a scanning electron microscope. Adhesion energy of the typical graphene-silicon interface is measured to be 151±28 mJ/m2. The proposed method and our measurements provide insights in fabrication and reliability of microelectromechanical/nanoelectromechanical systems.


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol E. Mcgruer, George G. Adams, Yan Du

George G. Adams

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du May 2011

Separation Modes In Microcontacts Identified By The Rate Dependence Of The Pull-Off Force, L. Chen, Nicol Mcgruer, George Adams, Yan Du

Nicol E. McGruer

We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy (SEM) demonstrates that these two rate-dependent modes can be related to brittle and ductile separation modes. The former behavior is indicative of brittle separation, whereas the latter accompanies ductile separation. Thus by monitoring the rate dependence of the pull-off force, the type of separation mode can be identified during cycling without interrupting the test …


Effect Of Temperature On The Corrosion Behavior Of Mild Steel Upon Exposure To Palm Biodiesel Apr 2011

Effect Of Temperature On The Corrosion Behavior Of Mild Steel Upon Exposure To Palm Biodiesel

A.S. Md Abdul Haseeb

Recently biodiesel, as an alternative fuel is getting more significance to replace diesel fuel completely or partially. However, corrosion of automotive materials in biodiesel is a major concern as this can reduce engine life. This study aims to investigate the corrosion behavior of mild steel at three different temperatures such as room temperature, 50 and 80 °C. Static immersion tests in B0 (diesel), B50 (50% biodiesel in diesel), B100 (biodiesel) were carried out for 1200 h. At the end of the tests, corrosion characteristic was investigated by weight loss measurements and changes of the exposed metal surface. Fuels were analyzed …


Interfacial Reactions Between Sn-3.5 Ag Solder And Ni-W Alloy Films Jan 2011

Interfacial Reactions Between Sn-3.5 Ag Solder And Ni-W Alloy Films

A.S. Md Abdul Haseeb

Nickel based alloys are currently being investigated in an effort to develop stable barrier films between lead free solder and copper substrate. In this study, interfacial reactions between Ni-W alloy films and Sn-3.5 Ag solder have been investigated. Ni-W alloys films with tungsten content in the range of 5.0-18.0 at.% were prepared on copper substrate by electrodeposition in ammonia citrate bath. Solder joints were prepared on the Ni-W coated substrate at a reflow temperature of 250 °C. The solder joint interface was investigated by Cross-sectional scanning electron microscopy, energy dispersive X-ray spectroscopy and electron back scatter diffraction. It has been …


Interfacial Reaction And Dissolution Behavior Of Cu Substrate In Molten Sn-3.8ag-0.7cu In The Presence Of Mo Nanoparticles Jan 2011

Interfacial Reaction And Dissolution Behavior Of Cu Substrate In Molten Sn-3.8ag-0.7cu In The Presence Of Mo Nanoparticles

A.S. Md Abdul Haseeb

Purpose - In electronic packaging, when solid copper comes in contact with liquid solder alloy, the former dissolves and intermetallic compounds (IMCs) form at the solid-liquid interface. The purpose of this paper is to study the effect of the presence of molybdenum nanoparticles on the dissolution of copper and the formation of interfacial IMC. Design/methodology/approach - Cu wire having a diameter of 250 μm is immersed in liquid composite solders at 250° up to 15 min. Composite solder was prepared by adding various amount of Mo nanoparticles into the Sn-3.8Ag-0.7Cu (SAC) solder paste. The dissolution behavior of Cu substrate is …


Relationship Of Surface Changes To Metal Leaching From Tungsten Composite Shot Exposed To Three Different Soil Types, Deborah Felt, Steven Larson, Chris Griggs, Catherine Nestler, Michelle Wynter Jan 2011

Relationship Of Surface Changes To Metal Leaching From Tungsten Composite Shot Exposed To Three Different Soil Types, Deborah Felt, Steven Larson, Chris Griggs, Catherine Nestler, Michelle Wynter

United States Army: Publications

Physical changes that occur on the surface of fired shots due to firing and impact with soil may increase the dissolution of muniton metals. Increased metal dissolution could potentially increase metal transport and leaching, affecting metal concentrations in surface and groundwater. This research describes the relationship between the surface changes on fired tungsten–nickel–iron (94% W:2% Ni:4% Fe) composite shots and metals leaching from those shots. Tungsten composite shot was fired into, and aged in, three soil types (Silty Sand, Sandy Clay, and Silt) in mesoscale rainfall lysimeters to simulate live-fire conditions and subsequent interactions between the metals of the composite …


Failure Analysis Of Retrieved Uhmwpe Tibial Insert In Total Knee Replacement Dec 2010

Failure Analysis Of Retrieved Uhmwpe Tibial Insert In Total Knee Replacement

A.S. Md Abdul Haseeb

This study involves the failure analysis of an ultra high molecular polyethylene (UHMWPE) tibial insert from Apollo® Total Knee System, which was removed after 10. years of service from 70. years old female patient. The tibial insert was investigated by using a stereoscope, scanning electron microscope (SEM), infinite focus microscope (IFM) and energy disperse spectroscopy (EDS) to characterize the morphology and composition of the bearing surface. Differential scanning calorimetry (DSC) and Fourier transform spectroscopy (FTIR) were employed to characterize the degradation and crystallinity of the component. Gel-permeation chromatography (GPC) was used to measure the polyethylene tibial insert molecular weight. Results …