Micro-Hardness and Micro-Wear Measurements on Magnetic Heads

Nanotribology ◽  
2003 ◽  
pp. 377-386
Author(s):  
V. Prabhakaran ◽  
F. E. Talke ◽  
J. T. Wyrobek
Keyword(s):  
Micro Hardness

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.

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.

scholarly journals Investigation of the microstructure evolution in TP347HFG austenitic steel at 700°C and its characterization method

2021 ◽  
Vol 40 (1) ◽  
pp. 12-22
Author(s):  
Yuetao Zhang ◽  
Tingbi Yuan ◽  
Yawei Shao ◽  
Xiao Wang
Keyword(s):  
Austenitic Steel ◽  
Aging Time ◽  
Microstructure Evolution ◽  
Precipitate Phase ◽  
Dispersion Strengthening ◽  
Micro Hardness ◽  
Dispersed Particles ◽  
Nonlinear Ultrasonic ◽  
The Matrix ◽  
Solution Strengthening

Abstract This article reports the microstructure evolution in TP347HFG austenitic steel during the aging process. The experiments were carried out at 700°C with different aging time from 500 to 3,650 h. The metallographic results show that the coherent twin and incoherent twin are existed in the original TP347HFG grains, while they gradually vanished with the increase of the aging time. After aging for 500 h, a lot of fine, dispersed particles precipitated from the matrix, but they disappeared after aging for 1,500 h. When the aging time extend to 3,650 h, the precipitates appeared apparently coarse in TP347HFG steel, which include the M23C6 and σ phase; besides, the micro-hardness of TP347HFG also changes during the aging, which was closely related to the effect of dispersion strengthening and solution strengthening. The results of the nonlinear ultrasonic measurement reveal that the β′ of TP347HFG steel was also changed with the aging time. It first increased at 0–500 h, then reduced later, and increased finally at 1,500–3,650 h. The variation of β′ in TP347HFG was influenced by a combined effect of the twin microstructure and the precipitate phase, which indicate that the nonlinear ultrasonic technique can be utilized to characterize the microstructure evolution in TP347HFG.

Study on Arc Ion Plating Nitride Films of Microscopic Morphology and Micro-Hardness

2011 ◽  
Vol 306-307 ◽  
pp. 274-279
Author(s):  
Qing Tao ◽  
Yan Wei Sui ◽  
Sun Zhi ◽  
Wei Song
Keyword(s):  
Thin Films ◽  
Steel Substrate ◽  
Nitride Film ◽  
Composition Analysis ◽  
Micro Hardness ◽  
Arc Ion Plating ◽  
Ion Plating ◽  
Tin Thin Films ◽  
Research Procedure ◽  
Microscopic Morphology

AlN and TiN thin films are widely used in electronic devices and acoustic material and other fields because of its unique merit, the preparation of nitride thin films by using the arc ion plating has not been a systematic and deep study. The article presents our research procedure which the AlN and TiN thin films are deposited on stainless steel substrate by arc ion plating (AIP). The characteristics of thin films, for example microstructure, morphology, composition analysis and hardness, are examined and analyzed. The results showed that: Droplet-like particles appear in the microstructure of nitride thin films, and the grain size of droplet-like particles in AlN thin films is greater than in TiN thin films. The micro-hardness of nitride films preparation in experiment has improved significantly, and establish firmly basic for extending the application field of nitride film.

Study on the Fine Grain size and the Micro‐Hardness at the Interface of AZ31/Mg‐Y Composites

2021 ◽  
Author(s):  
Yihong Xian ◽  
Weijun He ◽  
Wenhuan Chen ◽  
Zejun Chen ◽  
Bing Jiang ◽  
...  
Keyword(s):  
Grain Size ◽  
Micro Hardness ◽  
Fine Grain

scholarly journals Influence of Salt Support Structures on Material Jetted Aluminum Parts

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4072
Author(s):  
Benedikt Kirchebner ◽  
Maximilian Ploetz ◽  
Christoph Rehekampff ◽  
Philipp Lechner ◽  
Wolfram Volk
Keyword(s):  
Molten Salts ◽  
Laser Scanning ◽  
Water Soluble ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Support Structures ◽  
Micro Hardness ◽  
X Ray ◽  
Melting Temperatures ◽  
Economic Support

Like most additive manufacturing processes for metals, material jetting processes require support structures in order to attain full 3D capability. The support structures have to be removed in subsequent operations, which increases costs and slows down the manufacturing process. One approach to this issue is the use of water-soluble support structures made from salts that allow a fast and economic support removal. In this paper, we analyze the influence of salt support structures on material jetted aluminum parts. The salt is applied in its molten state, and because molten salts are typically corrosive substances, it is important to investigate the interaction between support and build material. Other characteristic properties of salts are high melting temperatures and low thermal conductivity, which could potentially lead to remelting of already printed structures and might influence the microstructure of aluminum that is printed on top of the salt due to low cooling rates. Three different sample geometries have been examined using optical microscopy, confocal laser scanning microscopy, energy-dispersive X-ray spectroscopy and micro-hardness testing. The results indicate that there is no distinct influence on the process with respect to remelting, micro-hardness and chemical reactions. However, a larger dendrite arm spacing is observed in aluminum that is printed on salt.

Double-pulse femtosecond laser peening of aluminum alloy AA5038: Effect of inter-pulse delay on transient optical plume emission and final surface micro-hardness

2016 ◽  
Vol 109 (21) ◽  
pp. 211902 ◽  
Author(s):  
E. I. Ageev ◽  
V. Yu. Bychenkov ◽  
A. A. Ionin ◽  
S. I. Kudryashov ◽  
A. A. Petrov ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Femtosecond Laser ◽  
Double Pulse ◽  
Laser Peening ◽  
Micro Hardness ◽  
Pulse Delay ◽  
Final Surface ◽  
Plume Emission

Influence of Melt Temperature on Compressive Plasticity of a Cu-Zr-Al Bulk Metallic Glass

2010 ◽  
Vol 146-147 ◽  
pp. 517-521
Author(s):  
Sheng Hui Xie ◽  
Xie Rong Zeng ◽  
Dong Ju Fu ◽  
Lei Zhao ◽  
Qiang Hu
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Metallic Glasses ◽  
Mechanical Performance ◽  
Casting Temperature ◽  
Thermal And Mechanical Properties ◽  
Micro Hardness ◽  
Melt Temperature ◽  
Hardness Tests ◽  
Important Solution

Cu47.5Zr47.5Al5 bulk metallic glasses (BMGs) were cast from the melt temperature 1143 to 1373 K. The structure, thermal and mechanical properties of the BMGs were investigated by XRD, DSC, HRTEM, dilatometric measurements, micro-hardness tests and uniaxial compression. The results indicate that the microstructure and mechanical performance of BMGs are closely affected by the casting temperature. Proper casting temperature ensures the BMGs with large relaxed excess free volume (REFV) and nano-crystallites, which favor the plastic deformation in Cu47.5Zr47.5Al5 BMGs. Regulating the preparing parameters is an important solution to good plasticity in BMGs.

Microstructure and Grain Abrasion Properties of Cr3C2-NiCr Coating Prepared by Laser Cladding Method

2012 ◽  
Vol 271-272 ◽  
pp. 3-7
Author(s):  
Long Wei ◽  
Zong De Liu ◽  
Xin Zhi Li ◽  
Ming Ming Yuan ◽  
Cheng Yuan Zhong
Keyword(s):  
Wear Resistance ◽  
Wear Rate ◽  
Laser Cladding ◽  
Micro Hardness ◽  
High Quality ◽  
Wear Resistant ◽  
Hardness Tester ◽  
Technology Analysis ◽  
Main Component

Cr3C2-NiCr has high quality of wear resistant properties and is widely used in abrasive environment. In this paper, Cr3C2-NiCr coating was prepared on 45 steel by laser cladding technology. Analysis and research of the coatings were achieved by SEM and XRD to determine the main component and the different region on coatings. The hardness and the element component were investigated by micro-hardness tester and EDS. Abrasion tests were performed to contrast the wear resistance of two materials. The results indicate that the hardness of the coatings is nearly 3 times as the substrate. The coatings are well combined with the substrate and the phase of Cr3C2 has a large proportion in the coatings. Abrasion tests show that the average of wear rate on substrate is 5.2 times as the coatings.

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