Anab initiocalculation of the ideal tensile strength of β-silicon nitride

2001 ◽  
Vol 64 (17) ◽  
Author(s):  
Shigenobu Ogata ◽  
Naoto Hirosaki ◽  
Cenk Kocer ◽  
Hiroshi Kitagawa
1991 ◽  
Vol 57 (539) ◽  
pp. 1637-1642 ◽  
Author(s):  
Shoji HARADA ◽  
Nao-Aki NODA ◽  
Osamu UEHARA ◽  
Mitsuyoshi NAGANO

2015 ◽  
Vol 744-746 ◽  
pp. 1566-1569
Author(s):  
Xian Zhong Chen

Magnetorheological rubber material is a kind of composite material of magneto elastic coupling with multi functions, which is composed of magnetic particles and the mixed rubber films with the magnetic properties of the material, but because of its mechanical properties has limited practical use, and nylon cloth which has the advantages of high strength, dimensional stability, can be the ideal framework of magnetorheological rubber. The results show that for the magnetorheological rubber made from the NR/SBR blend, the tensile strength of the magnetorheological rubber with the cord fabric can greatly improve, the tensile strength can reach 17.8MPa, but also can improve the shear modulus of magnetorheological rubber and zero field storage shear modulus.


2019 ◽  
Vol 116 (2) ◽  
pp. 219 ◽  
Author(s):  
Junjun Cui ◽  
Liqing Chen ◽  
Yanfei Li ◽  
Jiahua Liu ◽  
Jiaqi Xie

In order to improve mechanical properties of roll cast 8011 aluminum alloy (AA 8011) by grain strengthening, and expand its application field, the effect of different annealing treating processes on mechanical properties and microstructures of cryogenic rolled AA 8011 was investigated. The roll cast AA 8011 was cryogenic rolled for six passes and then annealed. The annealing treatment was adopted at 100–300 °C for 1 h, and then the annealing treatment was adopted at 220 °C for 10–80 min. The microstructures of AA 8011 under roll cast and cryogenic rolled states were studied by using OM. The grain size was calculated by the Image-pro-plus 5.0. The microstructures of AA 8011 under annealing states were observed by using TEM and energy dispersive spectrum analysis. The results show that the second phase Al8Fe2Si appears in the cryogenic rolled AA 8011 after annealing treatment. When the dislocation moves in the grain, the dislocation plays a pinning role, which is conducive to grain refinement. The optical annealing treatment was treated at 220 °C for 40 min with optimal thermal stability. The ideal grain size is 1 μm, hardness is 65 HV, and tensile strength is 202 MPa. It is about 1.5 times of the roll cast AA 8011.


In this paper we present computer calculations of the ideal strength of crystals of sodium chloride and argon, for a variety of modes of homogeneous deformation. As models of the interatomic binding we employ the simple, two-body, central-force Born-Mayer and Lennard-Jones potentials respectively. The calculations for argon are appropriate to absolute zero, those for sodium chloride to room temperature. The results indicate a very marked anisotropy of the ideal tensile strength for sodium chloride, with a pronounced minimum at <100>, which is consistent with the observed cleavage on this plane. The ideal tensile strength of argon is shown to be much less dependent on orientation, which accords with the lack of any obvious cleavage plane in this material. We also make some estimates of the ideal shear strength, and find this to be a minimum for {111} <112> shear for both argon and sodium chloride.


2003 ◽  
Vol 67 (3) ◽  
Author(s):  
Cenk Kocer ◽  
Naoto Hirosaki ◽  
Shigenobu Ogata

Author(s):  
Anton TIMOSHIN ◽  
Nikolay MITIN ◽  
Alexander OLEYNIKOV ◽  
Maria TIMOSHINA ◽  
Evgeniya MITINA

Dentistry is a part of medicine, where various polymer materials were used for the first time. Many factors forced researchers to find more stable, versatile, and hygienic materials for the manufacture of dental products. It is important to note that the search for the ideal polymer dental material is still ongoing. This is because modern polymers, in some cases, do not meet the specified requirements for chemical, physical, strength, and elastic properties. Based on the data on the method of creating and using silicone material for the base of the removable prosthesis "Gossil", an improved silicone material for two-layer dentures "Silep" was developed, as well as a special primer for better connection of the lining with the rigid acrylic base of the prosthesis. To evaluate the most suitable compound, materials were tested for several parameters, such as tensile strength, elongation, and shore hardness. In addition to selecting a suitable material for modification, the selection and testing of an adhesive that allows the chemical bonding of the acrylate surface to the siloxane surface were carried out.


2005 ◽  
Vol 23 (1) ◽  
pp. 88-94
Author(s):  
Masako NAKAHASHI ◽  
Toshiaki ITO ◽  
Yasushi GOTO ◽  
Yuji YASUDA ◽  
Xia ZHU ◽  
...  

1990 ◽  
Vol 25 (6) ◽  
pp. 2990-2996 ◽  
Author(s):  
Tatsuki Ohji ◽  
Yukihiko Yamauchi ◽  
Wataru Kanematsu ◽  
Shoji Ito

2008 ◽  
Vol 1086 ◽  
Author(s):  
Yoshitaka Umeno

AbstractAb initio density functional theory (DFT) calculations were performed to examine various factors which may influence the ideal strength, namely multiaxial loading condition and structure with low symmetry. First, the effect of normal stress on the ideal shear strength (ISS) in covalent crystals, Si, C, Ge and SiC, was evaluated. It was found that the response of ISS to normal stress differs depending on the material, while in metals the trend is unchanged. Obtained ISS as a function of normal stress is useful to understand criteria of dislocation nucleation in a pristine crystal because local lattices at the nucleation site undergo superimposed stress components in experiment. Secondly the ideal tensile strength of silicon surface was evaluated to examine how atomistic-level structure affects the mechanical property. The theoretical tensile strength of Si nanofilms with (100) surface, which is flat with dimer-row structures, shows only 20-30% reduction even though the thickness is down to 1 nm, meaning that the flat surface possesses high strength.


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