Wyniki wyszukiwania - Biblioteka Nauki

1

Effect of the type of aging after supersaturating on hardness and AW-7020 stop structure

100%

Abramczyk N. , Żuk D.

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2018

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tom Vol. 25, No. 3

9--16

EN

Effect of the type of aging after supersaturating on hardness and AW-7020 stop structure

2

The use of parametric structure modelling in the design process

80%

Żuk D. , Abramczyk N. , Lesnau A.

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2018

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tom Vol. 25, No. 3

541--548

EN

Automation of processes related to design and manufacturing is one of the essential goals of most manufacturing companies. The use of modern computer-aided design systems CAD allows partial automation of such processes. The parametric model can be built in some CAD systems. In the parametric model, selected dimensions are treated as control parameters. By changing the values of these parameters, we can control the remaining geometrical dimensions of the model. These dimensions can be associated with linear control parameters using mathematical relationships. Parameterization allows you to associate a geometric model with a mathematical model and allows you to automatically make changes to all elements associated with the currently modified parameter. When working on a non-parameterized model, the changes in the modelled object must be applied separately for each part and subassembly of which it is composed. In a parametric model, changing one parameter entails changes in other parameters dependent on it. Parameterization of the model allows its use for further modification of the designed structure related to customer requirements, even for that very complex, as well as accelerating the design process itself. The article presents a three-dimensional geometric model of a boat davit created with the use of the Siemens NX 9.0 software. In the work, the geometry of the crane model was parameterized for the assumed values of its height and reach. As a result of parametric modelling, the values of the individual geometric dimensions of the device’s structure elements and their mass were obtained. It was justified that thanks to the use of parameterized models, the time of design and construction processes can be significantly reduced, which makes the process more efficient.

3

Statistical methods in the analysis of strength parameters of epoxy-glass composites modified with rubber recyclate

80%

Drewing S. , Abramczyk N. , Żuk D. , Dyl T.

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tom Vol. 117, nr 2

71--78

EN

Purpose: The article presents a statistical analysis of strength parameters of newly developed epoxy-glass composite materials modified with the addition of rubber recyclate. Design/methodology/approach: Three variants of materials with a percentage of recyclate content in the composite matrix of 3%, 5%, 7% and a reference variant without the addition of recyclate were used for the study. The samples were subjected to an impact test on a ZWICK RKP 450IR-GE impact hammer. Resilience measurement values were subjected to statistical analyses at the significance level α = 95%, such as: testing the normality of distributions with the Shapiro-Wilk test, testing differences between pairs with the Student's t-test for dependent groups, and testing ANOVA differences for independent groups. Findings: The Shapiro-Wilk test confirmed that the resilience variables for all tested samples were in normal distributions; therefore the highest power parametric tests were used to test the differences. Using the Student's t-test, it was confirmed that between pairs of variables in configurations: standard sample with the modified sample, there were significant statistical differences in the distribution of resilience values for all samples. ANOVA confirmed significant changes in impact strength in 10 comparison variants. Research limitations/implications: The obtained test results showed that in 9 compared cases, there were significant statistical differences, and in one case, there were no significant differences. Practical implications: The performed statistical analyses confirmed their significant usefulness in the process of qualification of strength parameters for materials with high anisotropy, such as composites. Originality/value: The manufactured products are innovative in terms of the method of using the addition of rubber recyclate as a filler for epoxy-glass composites. The use of static methods for their study also has practical value. It optimizes the analysis methods of the results of measurements of strength parameters of new composite materials.

4

Influence of the type of layered distribution of rubber recyclate as an additive modifying the mechanical properties of epoxy-glass composites

80%

Abramczyk N. , Żuk D. , Panasiuk K. , Dyl T.

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tom Vol. 118, nr 2

61--66

EN

Purpose: The research aimed to determine the effect of adding rubber recyclate as a sandwich layer of sandwich composites made based on glass mat and epoxy resin EPO 652. Design/methodology/approach: Four types of research materials with a 5% addition of rubber recyclate and with different ways of layer distribution in the composite and one variant without the addition of recyclate as a comparative material were produced for the study. Samples made of the materials in question were subjected to a static tensile test to determine the changes in strength parameters caused by the addition and distribution of the modifier. Findings: Four types of research materials with a 5% addition of rubber recyclate and with different ways of layer distribution in the composite and one variant without the addition of recyclate as a comparative material were produced for the study. Samples made of the materials in question were subjected to a static tensile test to determine the changes in strength parameters caused by the addition and distribution of the modifier. Research limitations/implications: As a result of the conducted research, the fundamental influence of the recyclate additive and its distribution method on the changes in parameters recorded during the static tensile test was clearly found. Practical implications: The analyses carried out enable the selection of the optimal material variant depending on the intended application. Originality/value: The analysis of the preliminary results obtained during the research showed that epoxy-glass composites based on EPO 652 resin with the addition of rubber recyclate in the form of two and three sandwich layers have better strength parameters than the composite with random addition of recyclate to the matrix. The material characterized by the highest plasticity is a variant with two layers of recyclate spacers. At the same time, it can be stated that the highest values of relative deformation ε obtained a composite with one sandwich layer of rubber recyclate.