Evaluation of the Resistance of Individual Si Die to Cracking

1998 ◽  
Author(s):  
R. Berriche ◽  
R.K. Lowry ◽  
M.I. Rosenfield
Keyword(s):  
Thermal Cycling ◽  
Hardness Test ◽  
Mechanical Stresses ◽  
Test Method ◽  
Processing Conditions ◽  
Micro Hardness ◽  
Test Methodology ◽  
Vickers Micro Hardness

Abstract The present work investigated the use of the Vickers micro-hardness test method to determine the resistance of individual die to cracking. The results are used as an indicator of resistance to failure under the thermal and mechanical stresses of packaging and subsequent thermal cycling. Indentation measurements on die back surfaces are used to determine how changes in wafer backside processing conditions affect cracks that form around impressions produced at different loads. Test methodology and results obtained at different processing conditions are discussed.

scholarly journals Morphology and metallurgical studies on a few archeological samples found in old forges in Japan

2013 ◽  
Vol 37 (1) ◽  
pp. 43-50
Author(s):  
AK Das ◽  
I Kamal
Keyword(s):  
Iron Oxides ◽  
Natural Environment ◽  
Hardness Test ◽  
Hardness Measurement ◽  
Spectroscopy Study ◽  
Micro Hardness ◽  
X Ray ◽  
Naked Eye ◽  
Academy Of Sciences ◽  
Vickers Micro Hardness

An investigative study was carried out on a few archeological samples collected from very old and abandoned forges situated near Izumo city of Shimane prefecture in Japan. The samples were named as Koedo Tatara (in Japanese) and identified as Koedo-21, Koedo-39 and so on, as per the number of well dug for hunting the samples. In the naked eye observation the samples were looked like the rusted iron lump of heterogeneous shapes having brownish and blackish colours. A variety of minerals such as ilmenite (FeO.TiO2), fayalite (2FeO.SiO2), hercinite (2FeO.Al2O3) along with ferrite (FeO) were identified by observing the structural morphologies in optical microscopic study. EDS (Energy dispersive X-ray spectroscopy) study revealed that most of the samples were the composite of iron oxides along with a few amount of carbon, silica (SiO2), alumina (Al2O3), rutile (TiO2) etc. Vickers micro-hardness test revealed that several samples were moderately hard and some others were nonmetallic oxides and not fit for hardness measurement. It was realized that the samples were the by-product of old blacksmith’s forges which were dismantled for hundreds of years in the natural environment. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15679 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 43-50, 2013

Effect of Surface and Grain Boundary on the Reversion of Al-Zn Alloys

2014 ◽  
Vol 794-796 ◽  
pp. 1211-1216
Author(s):  
Keiyu Nakagawa ◽  
Teruto Kanadani
Keyword(s):  
Grain Boundary ◽  
Hardness Test ◽  
Age Hardening ◽  
Micro Hardness ◽  
Zn Alloy ◽  
Vickers Micro Hardness ◽  
Zn Alloys ◽  
Effective Source ◽  
Effect Of Surface

Age-hardening of Al-Zn alloy after quenching develops inhomogeneously due to the effect of surface as a vacancy sink and grain boundary as an easy path. In this study, reversion of the age-hardened Al-Zn alloys, in which ellipsoidal GP zones were formed, was investigated by Vickers micro-hardness test. Ellipsoidal GP zones were reverted more quickly near the surface and grain boundary than in the interior, as spherical GP zones in Al-10%alloy did. It is considered that the surface and grain boundary plays a role of effective source for vacancies, in addition to the interior source such as dislocations, as in the case of the reversion of spherical GP zones.

Micro-Hardness and Adhesion of Boron Carbon Nitride Coatings

1997 ◽  
Vol 11 (16n17) ◽  
pp. 749-756 ◽  
Author(s):  
Hou Qingrun ◽  
J. Gao
Keyword(s):  
Carbon Nitride ◽  
Pulsed Laser ◽  
Hardness Test ◽  
Laser Deposition ◽  
Micro Hardness ◽  
Nitride Coatings ◽  
Quartz Substrates ◽  
Boron Carbon Nitride ◽  
Vickers Micro Hardness ◽  
Boron Carbon

Boron carbon nitride coatings have been synthesized by the pulsed laser deposition method. Vickers micro-hardness and adhesion of the coatings were studied. A new model was applied to determine the hardness of the coatings which were too thin to be directly measured by the Vickers micro-hardness test. An intermediate layer of silicon was used to enhance the adhesion of the coatings on stainless steel, glass, and quartz substrates.

Corrosion Behavior of Al-Cu-Ni-Y Alloys

2013 ◽  
Vol 795 ◽  
pp. 535-539
Author(s):  
M.N. Derman ◽  
M.R. Jeffry ◽  
R. Kumar
Keyword(s):  
Corrosion Rate ◽  
Corrosion Behavior ◽  
Polarization Resistance ◽  
Dendritic Structure ◽  
Hardness Test ◽  
Longitudinal Direction ◽  
Micro Hardness ◽  
Ni Alloys ◽  
Microstructure Observation ◽  
Vickers Micro Hardness

Al based alloy has been widely used in various industries. This research paper aims at the investigation onto the effect of the percentage of Cu and Ni alloying elements in the corrosion behavior of Al-Cu-Ni alloys. The alloys were characterized by microstructural, physical properties, electrochemical, and phase analysis. Microstructure observation shows the alloys have transformed to dendritic structure. The addition of Ni reveals columnar twinned dendritic to the longitudinal direction of cast ingots. While the addition of Cu increases the density of the sample. The Vickers micro-hardness test shows that sample Al86-Ni5-Cu3-Y6 reached the optimum hardness value 51.36 HV. Tafel Plot performed shows that Al86-Ni5-Cu3-Y6 has the highest Polarization Resistance, Rp, 2 031.82 kΩ and lowest corrosion rate, 0.00380 mm per year. Alloy with high Rp value is highly resistant to corrosion.

scholarly journals Assessment of Sodium Thiosulfate Neutralizing Effect on Micro-hardness of Dentin Treated With Sodium Hypochlorite

2020 ◽  
Author(s):  
Safoora Sahebi ◽  
fereshteh Sobhnamayan ◽  
Mohammadhasan Naseri ◽  
Fariborz Moazami
Keyword(s):  
Sodium Hypochlorite ◽  
Normal Saline ◽  
Sodium Thiosulfate ◽  
Hardness Test ◽  
Control Group ◽  
P Value ◽  
Pairwise Comparisons ◽  
Micro Hardness ◽  
Neutralizing Agent ◽  
Vickers Micro Hardness

Abstract Background The aim of this study is to evaluate the ability of sodium thiosulfate (STS) to reverse the adverse effect of sodium hypochlorite (NaOCl) on dentin microhardness. Methods Fifty single-rooted teeth were decoronated and longitudinally sectioned. The samples were divided into a control and four sample groups (n = 20): Normal saline for 15 min as the control group, G1: 2.5% NaOCl for 15 min without an incubation period, G2: 2.5% NaOCl for 15 min, G3: 2.5% NaOCl for 15 min irrigated with normal saline followed by 5% Na2S2O3 for 10 min, G4: Normal saline for 15 min followed by 5% Na2S2O3 for 10 min. All groups except G1 were incubated for 1 week. The microhardness measurements were determined using the Vickers micro-hardness test. Data were analyzed using the Kruskal-Wallis test for pairwise comparisons. A p-value < 0.05 was considered significant. Results All groups showed a significant decrease in the micro-hardness value compared with the control group. NaOCl for 1 week (G2) reduced the micro-hardness of dentine compared with samples, tested immediately after immersion in NaOCl (G1) (p < 0.05). NaOCl alone (G2) or treated with Na2S2O3 (G3) resulted in a significant decrease in microhardness compared with the Na2S2O3 group (G4) (p < 0.05). Conclusions Sodium thiosulfate as a neutralizing agent could not prevent the microhardness downturn caused by sodium hypochlorite

scholarly journals Mechanical Behavior and Microstructural Analysis of Molybdenum-TZM Alloy Subjected to Different Annealing Temperature

2020 ◽  
Vol 1 (1) ◽  
pp. 25-29
Author(s):  
Muhamad Anas Munawwar Ghazali ◽  
Mohd Azhar Harimon ◽  
Mohammad Sukri Mustapa
Keyword(s):  
Mechanical Properties ◽  
Grain Boundary ◽  
Annealing Temperature ◽  
Microstructural Analysis ◽  
Hardness Test ◽  
Optical Microscope ◽  
Recrystallization Temperature ◽  
Micro Hardness ◽  
Annealing Heat Treatment ◽  
Vickers Micro Hardness

Mo-TZM alloy is one of the most famous economic molybdenum-based alloys. The percentage of chemical composition in mass of Mo-TZM alloy are Mo-0.5Ti-0.08Zr-0.03C. By adding some Titanium and Zirconium so that the mechanical properties and recrystallization temperature of molybdenum has been corresponding improvement. The purpose of this study is to determine the effect of different annealing temperature on mechanical properties of Mo-TZM alloy. The samples will be heated at two different temperature which are 1000 oC and 1300 oC in 1 hour and 40 minutes to change their microstructure behavior. The mechanical properties of the sample like hardness will be analyzed by using Vickers Micro hardness test. The force applied is 4.903 N and Vickers micro hardness number is 0.5 HVN for 10 second. Then to observe the microstructure changes, optical microscope and Scanning Electron Microscope (SEM) is be used. At annealing temperature 1000 oC, it show values of hardness is 249.54 VHN and the grain boundary size is 0.0898mm. While at annealing temperature 1300 oC, it show the lowest values of hardness which is 243.55 VHN and the highest grain boundary size which is 0.1068 mm. By doing annealing heat treatment it will decreases hardness values and increases the size of grain boundary

Microstructure and Properties of Diffusion Boride Layer on Die Steel

2011 ◽  
Vol 312-315 ◽  
pp. 788-793 ◽  
Author(s):  
Matej Beznák ◽  
Alexander S. Chaus ◽  
Lubomír Čaplovič
Keyword(s):  
Hardness Test ◽  
Hardness Measurement ◽  
Boride Layer ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Die Steel ◽  
X Ray ◽  
Depth Profiles ◽  
Boron Carbide B4c ◽  
Vickers Micro Hardness

Diffusion boride layer has been produced on the surface of a hot work tool steel. The microstructure and elemental spectra as well as depth profiles of the elements in the boride layer have been studied by scanning electron microscopy, X-ray diffraction analysis and energy dispersive X-ray spectrometry. Micro-hardness measurement was carried out using the Vickers micro-hardness test. The results showed that the boride layer is formed by boron compound Fe2B. Additionally, boron carbide B4C has been revealed embedded in the bulk of the boride layer.

scholarly journals Mechanical properties of materials used for temporary fixed dentures – in vitro study

2017 ◽  
Vol 30 (2) ◽  
pp. 61-64
Author(s):  
Elzbieta Celej-Piszcz ◽  
Leszek Szalewski ◽  
Przemyslaw Kleinrok ◽  
Janusz Borowicz
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
In Vitro Study ◽  
Hardness Test ◽  
Micro Hardness ◽  
Hardness Testing ◽  
Filling Materials ◽  
Temporary Filling ◽  
Vickers Micro Hardness

Abstract Objectives. The objective of the research was to define the mechanical properties of currently marketed temporary filling materials. Methods. Eight temporary filling materials: Boston, Dentalon, Protemp II, Revotek LC, Structure 2, Structure 3, UniFast LC, UniFast Trad were used to make 5 samples each of measurements 2 × 2 × 25 mm, in order to define the flexural strength, and 10 rings each of measurements 2 × 5 mm, in order to carry out the Vickers micro-hardness test. After preparation, the samples were stored in distilled water of temperature of 370°C, for 7 days. Subsequently, flexural strength and Vickers hardness testing was undertaken. Results. Composite temporary materials showed considerably better mechanical properties, both in flexural strength and in Vickers micro-hardness testing. Conclusions. the best mechanical properties, both in terms of flexural strength, as well as Vickers micro-hardness test can be observe among composite materials.

Micro-Hardness and Morphology of LDPE Influenced by Beta Radiation

2014 ◽  
Vol 606 ◽  
pp. 253-256 ◽  
Author(s):  
Martin Ovsik ◽  
Petr Kratky ◽  
David Manas ◽  
Miroslav Manas ◽  
Michal Stanek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Hardness Test ◽  
Polymer Materials ◽  
Beta Radiation ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Depth Sensing ◽  
Surface Layers ◽  
Hardness Values ◽  
Different Doses

This article deals with the influence of different doses of Beta radiation to the structure and mico-mechanical properties of Low-density polyethylene (LDPE). Hard surface layers of polymer materials, especially LDPE, can be formed by radiation cross-linking by β radiation with doses of 33, 66 and 99 kGy. Material properties created by β radiation are measured by micro-hardness test using the DSI method (Depth Sensing Indentation). Individual radiation doses caused structural and micro-mechanical changes which have a significant effect on the final properties of the LDPE tested. The highest values of micro-mechanical properties were reached at radiation dose of 66 and 99 kGy, when the micro-hardness values increased by about 21%. The changes were examined and confirmed by X-ray diffraction.

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