Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Hardness

Discipline
Institution
Publication Year
Publication
Publication Type
File Type

Articles 91 - 101 of 101

Full-Text Articles in Engineering

The Influence Of Titanium And Cerium On Microstructure And Properties Of Fe-C-Cr-Nb Alloys, Zeljko J. Kamberovic Jan 2005

The Influence Of Titanium And Cerium On Microstructure And Properties Of Fe-C-Cr-Nb Alloys, Zeljko J. Kamberovic

Zeljko J Kamberovic

In this paper, the influence of titanium and cerium on the microstructure and properties of Fe- C-Cr-Nb alloys are examined, in both as-cast and heat treated state. These elements affect the crystallisation process of Fe-C-Cr-Nb alloys and the transformation of austenite during the cooling process after solidification. Titanium changed the morphology of NbC carbides. Further, in the austenite of the examined Fe-C-Cr-Nb-Ti alloys, very fine particles of precipitated secondary carbide can be seen. The alloy containing 0,28%Ti and 0,19%Ce has martensite-perlite-austenitic matrix microstructure in as-cast condition. Adding titanium and cerium to Fe-C-Cr-Nb alloys will also changed its properties, since the …


Processing, Microstructure And Mechanical Behavior Of Nanocomposite Multilayers, Zuqiang Qi Jan 2004

Processing, Microstructure And Mechanical Behavior Of Nanocomposite Multilayers, Zuqiang Qi

LSU Doctoral Dissertations

Nanoscale multilayer coatings have high potential for numerous engineering applications because they can exhibit enhanced properties due to nanoscale effects and combine different properties from individual components. At present, scale effects on the mechanical behavior of multilayers are not well understood. Three multilayer nanocomposite systems, namely Al/Al2O3, Ti/TiN, and Cr/a-C, have been synthesized by using a dual-gun e-beam physical vapor deposition, to investigate the effect of layer thickness, the nature of components and their microstructures on the mechanical behavior. The deposited Al and Ti nanolayers were found to have polycrystalline fcc and hcp structure, respectively, the Cr and TiN layers …


On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film Dec 2002

On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film

A.S. Md Abdul Haseeb

A hard Fe-0.96 mass pet C alloy with a hardness value of 810 HV has been electrochemically synthesized from a ferrous sulfate bath containing a small amount of citric acid and L-ascorbic acid. The nature of the alloy has been investigated by a number of techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic measurements. The decomposition behavior of the alloy is also studied and compared with that of thermally prepared martensite. It has been found that the electrochemically deposited Fe-C alloy exists in …


On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film Nov 2002

On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film

A.S. Md Abdul Haseeb

A hard Fe-0.96 mass pet C alloy with a hardness value of 810 HV has been electrochemically synthesized from a ferrous sulfate bath containing a small amount of citric acid and L-ascorbic acid. The nature of the alloy has been investigated by a number of techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic measurements. The decomposition behavior of the alloy is also studied and compared with that of thermally prepared martensite. It has been found that the electrochemically deposited Fe-C alloy exists in …


Development Of Hardness Measurement Procedure For Nanocomposite Nc-Tin/A-Si3n4, Keba Moto Aug 2002

Development Of Hardness Measurement Procedure For Nanocomposite Nc-Tin/A-Si3n4, Keba Moto

Makara Journal of Technology

Hardness of nc-TiN/a-Si3N4 nanocomposites which was determined by using two methods of measurements i. e. depth sensing method and remaining plastic indentation area that were magnified by using SEM (Scanning Electron Microscope) lie in the good agreement. The hardness value is not influenced by the biaxial and residual compressive stress. The measurement of the biaxial stress on the substrate shows a very small value of biaxial stress as well as the constant hardness and crystallite size against annealing temperature. Therefore, the reported hardness value here is the intrinsic value that depend on its microstructure properties.


Nanofatigue Studies Of Ultrathin Hard Carbon Overcoats Used In Magnetic Storage Devices, Xiaodong Li, Bharat Bhushan May 2002

Nanofatigue Studies Of Ultrathin Hard Carbon Overcoats Used In Magnetic Storage Devices, Xiaodong Li, Bharat Bhushan

Faculty Publications

A technique to perform nanofatigue experiments was developed. This technique utilizes a depth-sensing nanoindenter with harmonic force. The nanofatigue behavior of 20 nm thick amorphous carbon coatings was studied. The contact stiffness was monitored continuously throughout the test. The abrupt decrease in the contact stiffness indicates fatigue damage has occurred. The critical load amplitude, below which no fatigue damage occurs, was identified. It was found that the filtered cathodic arc coating exhibits longer fatigue life than a direct ion beam coating. Failure mechanisms of the coatings during fatigue are also discussed in conjunction with the hardness,elastic modulus, and fracture toughness, …


Effects Of Solidification Conditions And Heat Treatment On The Microstructure And Vickers Hardness Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Stanley G. Vermilyea, Efstratios Papazoglou, John C. Mitchell, Alan B. Carr Jan 1996

Effects Of Solidification Conditions And Heat Treatment On The Microstructure And Vickers Hardness Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Stanley G. Vermilyea, Efstratios Papazoglou, John C. Mitchell, Alan B. Carr

Cells and Materials

Two representative Pd-Cu-Ga dental alloys, one with a dendritic as-cast microstructure containing a eutectic interdendritic constituent and the other with an equiaxed fine-grained as-cast microstructure containing a near-surface eutectic constituent, have been subjected to rapid quenching following casting, in addition to the conventional bench cooling recommended by the manufacturers. The quenched alloys were subsequently heat treated at temperatures of 1200°, 1500° and 1800 op that span the range of the firing cycles for dental porcelain. Scanning electron microscopic examination showed that the lamellar eutectic constituents normally present in the microstructures of the as-cast and bench-cooled alloys persisted when the alloys …


Study Of The Wear Behaviour Of Al-4.5% Cu-3.4% Fe In Situ Composite: Effect Of Thermal And Mechanical Processing Aug 1995

Study Of The Wear Behaviour Of Al-4.5% Cu-3.4% Fe In Situ Composite: Effect Of Thermal And Mechanical Processing

A.S. Md Abdul Haseeb

Wear behaviour of as-cast and heat-treated spheroidal graphite (SG) cast iron has been studied under dry sliding conditions using a pin-on-disc type apparatus. Wear tests were carried out at a linear sliding speed of 0.88 m s -1, under a constant load of 1.5 kg. All tests were performed in ambient air at room temperature. Extent of wear damage and wear mechanisms were investigated by means of weight loss measurement, optical microscopy, microhardness measurement and X-ray diffractometry on wear debris. The wear rate measured after 9500 m of sliding is found to be about three times higher in the as-cast …


Measuring The Nanomechanical Properties And Surface Forces Of Materials Using An Atomic Force Microscope, Nancy Burnham, Richard Colton Jun 1989

Measuring The Nanomechanical Properties And Surface Forces Of Materials Using An Atomic Force Microscope, Nancy Burnham, Richard Colton

Nancy A. Burnham

An atomic force microscope(AFM) has been configured so that it measures the force between a tip mounted on a cantilever beam and a sample surface as a function of the tip–surface separation. This allows the AFM to study both the nanomechanical properties of the sample and the forces associated with the tip–surface interaction. More specifically, the AFM can measure the elastic and plastic behavior and hardness via nanoindentation,van der Waals forces, and the adhesion of thin‐film and bulk materials with unprecedented force and spatial resolution. The force resolution is currently 1 nanonewton, and the depth resolution is 0.02 nm. Additionally, …


Identification Of Kentucky Shales, Tommy C. Hopkins, Brian C. Gilpin Aug 1981

Identification Of Kentucky Shales, Tommy C. Hopkins, Brian C. Gilpin

Kentucky Transportation Center Research Report

Results obtained from a series of engineering tests performed on 40 different types of shales are summarized and discussed. Both hard and soft shales, as well as shales having well-documented histories of involvement in highway embankment failures and shales having little known involvement, were tested. A major portion of the report examines the suitability of the slake-durability tests, originally devised by Franklin-Chandra of England, as a means of broadly characterizing the engineering properties of Kentucky shales. Results obtained from ten different slake-durability testing procedures, which include procedures proposed by Franklin and Chandra and others as well as procedures devised during …


The Heat Treatment Of An Eight Percent Manganese-Titanium Alloy, Robert Alden Loucks Jun 1957

The Heat Treatment Of An Eight Percent Manganese-Titanium Alloy, Robert Alden Loucks

Bachelors Theses and Reports, 1928 - 1970

The subject of this particular investigation, manganese titanium alloy, has a sufficient amount of manganese present to retain beta upon quenching from the alpha plus beta or beta ranges. Thus, improvement of properties of this alloy is possible by selective heat treatments.