Thermomechanical behavior and microstructural evolution of SiNx/Al bimaterial microcantilevers

Since point defects have a limited solubility in the rutile (TiO2) lattice, small deviations from stoichiometry are known to produce crystallographic shear (CS) planes which accomodate local variations in composition. The material used in this study was porous polycrystalline TiO2 (60% dense), in the form of 3mm. diameter disks, 1mm thick. Samples were mechanically polished, ion-milled by conventional techniques, and initially examined with the use of a Siemens EM102. The electron transparent thin foils were then heat-treated under controlled atmospheres of CO/CO2 and H2 and reexamined in the same manner.The “as-received” material contained mostly TiO2 grains (∼5μm diameter) which had no extended defects. Several grains however, aid exhibit a structure similar to micro-twinned grains observed in reduced rutile. Lattice fringe images (Fig. 1) of these grains reveal that the adjoining layers are not simply twin related variants of a single TinO2n-1 compound. Rather these layers (100 - 250 Å wide) are alternately comprised of stoichiometric TiO2 (rutile) and reduced TiO2 in the form of Ti8O15, with the Ti8O15 layers on either side of the TiO2 being twin related.

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Corrosion Behavior and Microstructural Evolution of Magnesium Powder with Milling Time Prepared by Mechanical Milling

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2011.49.6.454 ◽

2016 ◽

Vol 49 (6) ◽

Keyword(s):

Corrosion Behavior ◽

Microstructural Evolution ◽

Mechanical Milling ◽

Milling Time ◽

Magnesium Powder

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The influence of Mo/B atomic ratio on microstructural evolution and mechanical properties of Mo2FeB2-based cermets

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.3139/146.111778 ◽

2019 ◽

Vol 110 (7) ◽

pp. 664-671

Author(s):

Jiajie Zhang ◽

Yong Zheng ◽

Wei Zhou ◽

Guotao Zhang ◽

Zheng Ke ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructural Evolution ◽

Atomic Ratio

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Temperature-Dependent Die Warpage Measurements Up to 400°C

ISTFA 2017: Conference Proceedings from the 43rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2017p0046 ◽

2017 ◽

Author(s):

Tobias Mittereder ◽

Bernhard Ferstl ◽

Terry Heidmann ◽

Christian Hollerith

Keyword(s):

Data Acquisition ◽

White Light ◽

State Of The Art ◽

Thermomechanical Behavior ◽

Temperature Dependent ◽

Optical Access

Abstract Temperature-dependent die warpage measurements show the possibility to analyze the thermomechanical behavior during assembly, e.g. within soldering processes. The warpage data acquisition is realized by confocal chromatic white light profilometry in combination with a precision heating/cooling chuck encapsulated in a chamber with optical access. The combination of these two tools allows precise die warpage evaluation under varied device temperature up to +400°C. This method helps to solve emerging challenges due to warpage during assembly of state of the art packages including thin dies and stacked dies as in e.g. 3D-SIPs.

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