Determination of the influence of halogens on the strength properties of metals

1985 ◽  
Vol 21 (1) ◽  
pp. 57-61
Author(s):  
B. B. Alchagirov ◽  
V. M. Yakovlev ◽  
Yu. A. Orkvasov ◽  
A. N. Bekrenev
Keyword(s):  
Author(s):  
Matylda Tankiewicz

Abstract In the paper the results of laboratory investigations of structure of layered soil are presented. They focus on varved clay that is a soil composed of two alternately arranged varves with different texture and mechanical properties. An effect of such structure is an anisotropy of the material. Due to varying conditions during its formation process the soil exhibits some irregularities in composition and structure. Due to that modelling of mechanical behavior, like strength, may not provide satisfactory results. Main purpose of the examinations is an investigation of internal structure of layered soil – varved clay – in relation to its strength anisotropy and evaluation of the suitability of the use of two different techniques to assess the soil structure. Investigated material have been taken from area near city of Bełchatów in central Poland. The examinations included investigation of particle size distribution of soil and its components, identification of lamination with use of scanning electron microscope (SEM) and computed microtomography technique (μCT). First, the texture of each varve and varved clay as a composite have been estimated. Next, the investigation of surface perpendicular to the lamination have been carried out with SEM. Pictures of varves with different magnifications are presented. Also the varves arrangement and details of layers contact area are shown. Finally, investigation of internal structure of the soil have been performed by using microtomograph. The outcome is a series of radiographic images and reconstructed 3D model of tested soil. Presented results show complexity of the structure of varved clay that affect the mechanical behavior. Determination of the structure with use of presented techniques may be helpful in examination of strength properties and proper modeling of such soil.


2019 ◽  
Vol 252 ◽  
pp. 08007 ◽  
Author(s):  
Jacek Góra ◽  
Danuta Barnat-Hunek ◽  
Paweł Wlaź ◽  
Monika Garbacz

The article presents the results of testing physical and strength properties of concrete with the addition of lightweight perlite in the amount of 10 and 20%. The additive was introduced by volume substituting a part of the sand. In addition, the effect of using siloxane admixtures and a vinyl acetate copolymer with different degree of dosing, as well as applied simultaneously, were analysed. The tests were carried out in the field of bulk density and proper density, determination of tightness and porosity, compressive strength and tensile strength after 28 days of maturation. In terms of durability of concrete, absorption and resistance of concretes to the freeze-up effects after 100 freezing and thawing cycles were tested. The results of the study were subjected to statistical analysis using the analysis of variance. The analysed factors of influence were the amount of perlite addition, as well as the type and amount of the added admixture


ce/papers ◽  
2018 ◽  
Vol 2 (2-3) ◽  
pp. 791-796
Author(s):  
Monika SULOVSKA ◽  
Jakub STACHO

2016 ◽  
Vol 687 ◽  
pp. 206-211
Author(s):  
Wojciech Więckowski

This study presents the findings of numerical simulations of forming process for an inspection hole cover with stiffening ribs made of thin grade 2 titanium sheet metal. The numerical simulation was carried out using the FEM method with PAMStamp 2G software. Numerical calculations were performed with consideration for the phenomenon of material strain hardening and anisotropy of plastic properties of the sheet metal formed. Properties of the grade 2 titanium alloy analysed in the simulations were adopted based on the results of the empirical studies. Adequate parameters of the forming process were selected in order to eliminate unfavourable phenomena of losing of material coherence and sheet metal wrinkling. The effect of conditions of friction between the sheet metal and tool and pressure force of the blank holder on the forming process was investigated. The analysis of the distribution of plastic strain and reduction in wall thickness of the drawn parts can be used for determination of the effect of changes in selected parameters and orientation of the specimen on the process of drawn part forming. The quality of drawn parts was assessed based on the shape inaccuracy determined during simulation of forming. The inaccuracy depended on the conditions of the process and strength properties of the titanium sheet metal.


2015 ◽  
Vol 31 (4) ◽  
pp. 308-315 ◽  
Author(s):  
M. F. Gong ◽  
F. Mei ◽  
S. R. Qiao ◽  
S. H. Wu ◽  
B. A. Lyashenko
Keyword(s):  

2014 ◽  
Vol 1020 ◽  
pp. 341-346
Author(s):  
Kamil Dubała ◽  
Jacek Selejdak

Wooden constructions are very susceptible to damage caused by improper operating conditions. Depending on the work conditions of construction the consumption manifest itself through: growth of cracks, loose connections, exceeding the allowable diffracts, constant moisture, development of fungus and mold, the occurrence of pests. Determining the type of these defects and their impact on work conditions is the topic of this article. Determination of strength properties of the component consist on establishing the type and kind of wood used in the construction and its class making it is possible to assign standardized permissible stress values and the modulus of elasticity. Determination of the extent to which the original cross-section of the component has been damaged during operation (shallow or deep crack, shrinkage crack, damage of internal structure of the wood by insects and fungus, moisture) allows to determine how much the strength properties of the wood component has been deteriorated. The static-strength analysis aims to determine the actual strength of load capacity of the component and stability of the whole object after taking into account the adverse impact of consumption and damage of the construction and allows determining and selecting suitable variant of renovation, repair or enhance the construction of the object. The article depicted the methods of determining the rate of consumption of the construction and taking into account the effect of cracks, moisture, fungi and insects action on the load capacity of wooden components..


TAPPI Journal ◽  
2020 ◽  
Vol 19 (2) ◽  
pp. 71-85
Author(s):  
GUSTAV MARIN ◽  
MIKAEL NYGARDS ◽  
SOREN OSTLUND

Five commercial multiply folding boxboards made on the same paperboard machine have been analyzed. The paperboards were from the same product series but had different grammage (235, 255, 270, 315, 340 g/m2) and different bending stiffness. The paperboards are normally used to make packages, and because the bending stiffness and grammage varies, the performance of the packages will differ. Finite element simulations can be used to predict these differences, but for this to occur, the stiffness and strength properties need to be deter-mined. For efficient determination of the three-dimensional properties in the machine direction (MD), cross direction (CD), and Z direction (ZD), it is proposed that the paperboard should be characterized using in-plane tension, ZD-tension, shear strength profiles, and two-point bending. The proposed setups have been used to determine stiff-ness and strength properties at different relative humidity (20,% 50%, 70%, and 90% RH), and the mechanical proper-ties have been evaluated as a function of moisture ratio. There was a linear relation between mechanical properties and moisture ratio for each paperboard. When the data was normalized with respect to the standard climate (50% RH) and plotted as a function of moisture ratio, it was shown that the normalized mechanical properties for all paperboards coincided along one single line and could therefore be expressed as a linear function of moisture ratio and two constants. Consequently, it is possible to obtain the mechanical properties of a paperboard by knowing the structural prop-erties for the preferred level of RH and the mechanical property for the standard climate (50% RH and 23°C).


2021 ◽  
Vol 0 (1) ◽  
pp. 23-27
Author(s):  
I. S. Nefyolov ◽  
◽  
N. I. Baurova ◽  

The effect of negative temperatures on strength characteristics of plastic component joints (hot gas welding, gluing, 3D-welding) made with the use of additive technologies has been examined. It has been found out that 3D-wlding allows one to produce joints with the highest strength properties. It was shown that low temperature values (–30 °С) did not have the negative influence on strength properties of ABS-plastic joints but even increased them as compared with analogues samples tested at the room temperature.


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