Stability of Pure and Aln-Alloyed Al2OC and Influence on Abrasive Properties of Al2O3-A14C3-AlN Materials

1989 ◽  
pp. 613-620
Author(s):  
T. Zambetakis ◽  
J. M. Lihrmann ◽  
Y. Larrère ◽  
M. Daire
Keyword(s):  
Author(s):  
Balázs Czinder ◽  
Ákos Török

Abstract Aggregates are necessary materials for the construction industry. Owing to their favourable properties, andesites are frequently used rock materials; hence, the investigation of their mechanical and aggregate properties has great significance. This paper introduces the analyses of 13 Hungarian andesite lithotypes. The samples were collected from six andesite quarries in Hungary. Cylindrical specimens and aggregate samples with 10.0/14.0-mm-sized grains were made from rock blocks. The specimens were tested in dry, water-saturated and freeze–thaw subjected conditions. Bulk density, uniaxial compressive strength, modulus of elasticity, indirect tensile strength and water absorption were measured. The abrasion resistance was tested by micro-Deval tests. The flakiness indexes of the samples were also measured. The data set of the laboratory test results provided input for further, one- and two-variable statistical analyses. According to the test results, there is no significant difference between the strength parameters measured in water-saturated and in freeze–thaw subjected conditions. The correlation and regression analyses revealed relationships between some rock mechanical parameters, as well as between micro-Deval coefficient and uniaxial compressive strength.


2020 ◽  
Vol 142 ◽  
pp. 105984
Author(s):  
Enrico Casamassa ◽  
Ambra Fioravanti ◽  
Mauro Mazzocchi ◽  
Maria Cristina Carotta ◽  
Maria Giulia Faga
Keyword(s):  

1999 ◽  
Vol 566 ◽  
Author(s):  
Uday Mahajan ◽  
Marc Bielmann ◽  
Rajiv K. Singh

In this study, we have characterized the effects of abrasive properties, primarily particle size, on the Chemical Mechanical Polishing (CMP) of oxide films. Sol-gel silica particles with very narrow size distributions were used for preparing the polishing slurries. The results indicate that as particle size increases, there is a transition in the mechanism of material removal from a surface area based mechanism to an indentation-based mechanism. In addition, the surface morphology of the polished samples was characterized, with the results showing that particles larger than 0.5 μm are detrimental to the quality of the SiO2 surface.


Refractories ◽  
1995 ◽  
Vol 36 (8) ◽  
pp. 233-234 ◽  
Author(s):  
Yu. P. Udalov ◽  
E. E. Valova ◽  
S. S. Ordan'yan
Keyword(s):  

2021 ◽  
Author(s):  
Sebastian Els ◽  
Sara Almaeeini ◽  
Hamad Almarzooqi

<p>The Emirates Lunar Mission is developing the small and light weight "Rashid" rover. The goals for this rover are to traverse several hundred meters on the lunar surface during the course of one lunar day. The Rashid rover's science objectives cover both fundamental science as well as engineering topics with the goal to enable future missions to the lunar surface, and other airless solar system bodies. Hence, Rashid will carry a suite of scientific instruments and an experiment, covering a wide range of the physical properties at the lunar surface. The focus of investigation for the microscopic imager (CAM-M) will be to measure the regolith particle size distribution, and the lunar surface structure at microscopic scales. The Langmuir probe system (LNG) will address  the  electron density profile of the sheath, its behavior over the course of the lunar day, and its dependence on topographic features.  A thermal imager (CAM-T) with low spatial resolution is also foreseen. Finally, the in-situ testing of the adhesive and abrasive properties of various materials to lunar regolith is planned to be conducted by the MAD experiment.  In this paper the science program and instrumentation of the Rashid mission will be outlined. </p>


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