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A novel design for a specimen and a grip for tensile testing of 3D printed materials is proposed and investigated in the paper. The specimen design is based on ISO 527-2 standard and it is intended for the upright 3D printing and investigation of influence of the 3D printing orientation on the mechanical properties of the 3D printed material. Two specimens were 3D printed from PLA material and successfully tested in a tensile testing machine. Grips, made from 3D printed composite materials (onyx reinforced with graphite fibers), were designed and used for fixation of the specimen in the machine jaws. Obtained results for ultimate tensile strength were in the expected range for PLA material. [ABSTRACT FROM AUTHOR]

The paper describes the determination of the mechanical properties of the spherical floors of pressure vessels, obtained by the welding process and shaped by the process of gradual local deformation in the cold state, i.e. by the process of Incremental sheet forming (ISF). Spherical cylindrical bottoms are an integral part of most closed-pressure vessels. Cylindrical pressure vessel floors are made from one part, but the standards also allow for welded construction when the dimensions of the floors are larger than the standard dimensions of the sheet metal for production. Pressure vessel floors obtained by the welding process and shaped by the process of gradual local deformation in the cold state, i.e. by the process of incremental deformation, have a multiaxial initial stress state, which differs significantly from the initial stress state of the cylindrical part of the vessel. Checking the behavior of such floors before completing the vessel itself, i.e. before putting it into operation, is necessary, on the one hand, due to a large number of influencing factors, and on the other hand, due to the high cost of testing the real construction itself. The aim of the test is to determine the influence of the parameter: type of material, thickness, and diameter on the following quantities: mechanical properties, ReH, Rm, A5, and total energy used for impact, KV. [ABSTRACT FROM AUTHOR]

More recently modified stainless steels have been used to produce various structural elements that work in complex operating conditions. Stainless steel X8CrNiS18-9 (standard EN 10088-3: 2005) is the most commonly used austenitic stainless steel due to its good machinability. This steel has high mechanical and working properties thanks to complex alloying, primarily with the elements such as chromium and nickel. The content of sulphur present in the steel from 0.15 to 0.35% improves machinability. However, sulphur at the same time decreases the mechanical properties, particularly toughness. The addition of sulphur, which is the cheapest available additive for free machining, will impair not only the transverse strength and toughness but also the corrosion resistance. The aim of this work is to determine the influence of tellurium on the machinability, corrosion resistance and mechanical properties of the mentioned steel. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Particle size distribution measurements were performed on ground granulated blastfurnace slag by laser diffraction with the powder dispersed in distilled water with sodium hexametaphosphate used as dispersing agent, as well as in pure distilled water and propan-2-ol. Two samples of slag with Blaine fineness 4700 cm²/g and5500 cm²/g were tested. The results showed significant differences between results obtained by using different dispersants. Percentiles dv10 and dv50 are significantly lower when propan-2-ol or pure water were used instead of water with SHMP as dispersing agent. [ABSTRACT FROM AUTHOR]

Mine development imposes very high technical requirements of the mine hoisting equipment in terms of speed of transport. To meet these requirements it is necessary to properly design the structural elements of mine hoisting equipment which means that they must have the proper characteristics of the materials from which they are made such as mechanical properties. The suspension lever is an important fixing part of mining installations export container. Since the suspension levers are exposed to dynamic loads during operation, one of the most important test is a determination of their dynamical strength. This paper presents the determination of the dynamic strength of a new suspension lever and a suspension lever that has been in use for several years. Based on these parameters further working life of the suspension lever can be determined in order to increase the safety of the entire plant. [ABSTRACT FROM AUTHOR]

The basic characteristics of the chemical composition of steel with improved machinability (X8CrNiS18-9) are the increased content of sulphur (0.15-0.45%), phosphorus (0.07-0.11%) and manganese (0.5-1.5%). Sulphur by creating sulphide inclusions reduces friction and cutting resistance, and increases the brittleness of the chip. Considering its harmful effect in steel, as well as the fact that non-metallic inclusions have been insufficiently tested for this type of high-alloyed steel, the aim of this research is to determine by microalloying the possibility of modification of non-metallic inclusions. Modification with boron and zirconium favorably affects the ductile properties of steel, and a step forward in this study is a modification of inclusions with tellurium. It is of particular importance to determine the behavior of non-metallic inclusions in the process of production of the structural part and in subsequent exploitation. Therefore, plastic processing of austenitic stainless steel was also carried out, forging and rolling with two different level of processing. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

More recently a modified stainless steels have been used to produce various structural elements that work in complex operating conditions. Stainless steel X8CrNiS18-9 (standard EN 10088-3: 2005) is the most commonly used austenitic stainless steel due to its good machinability. This steel has high mechanical and working properties thanks to a complex alloying, primarily with the elements such as chromium and nickel. The content of sulfur present in the steel from 0.15 to 0.35% improves machinability. However, while sulfur improves machinability at the same time decreases the mechanical properties particularly toughness. The aim of this work is to determine the influence of boron, zirconium and tellurium on the mechanical properties the mentioned steel. Change of mechanical properties, depending on the chemical composition of the steel is simulated with MATLAB program. [ABSTRACT FROM AUTHOR]

Stainless steel plays an important role in all emerging technologies. Detrimental effects of inclusions in steel do not only depend on their sizes, shape, distribution, but also on their chemical composition and mechanical properties. For this reason, the control of formation of non metallic inclusions and the characterization present the basis of improvement of steel product properties and lead to sustainable development in design of new steel grades. In order to produce steels with better machinability, such as AISI 303 grades, a modification of inclusions with carefully designed chemical composition is presented. In this work detailed SEM/EDS analyses of inclusions - manganese sulphides modified by zirconium are presented. Also, the results of tests of machinability (cutting force and surface roughness) and impact energy for the melt without additions of alloying elements and with the addition of zirconium are presented. [ABSTRACT FROM AUTHOR]