The influence of injection molding on tensile and tear properties of EPDM rubber

In industry the control of physical properties of rubber products produced by injection molding is mostly performed on testing samples produced by another method-cutting out of a compression molded plate according to ISO standard. This different method of producing testing samples and final products may have a different impact on physical properties. The paper compares and evaluates the selected physical properties (tensile strength, modulus of elasticity and tear strength) of EPDM rubber samples prepared by the standard method (cutting out of a compression molded plate) and injection molded samples and finally third method-cutting out of an injection molded plate. The results have shown that using the injection molded samples we will achieve more objective results mainly to determine the tear strength. In the case of tensile strength, the differences are not so significant. © 2018, World Scientific and Engineering Academy and Society. All rights reserved

Polymer fluidity influenced by type and amount of filler

Delivery of polymer melts into the mold cavity is the most important stage of the injection molding process. This paper shows the influence of cavity surface roughness and technological parameters on the flow length of polymers into mold cavity. Application of the measurement results may have significant influence on the production of shaping parts of the injection molds especially in changing the so far used processes and substituting them by less costly production processes which might increase the competitiveness of the tool producers and shorten the time between product plan and its implementation. This research focused into the influence of technological parameters on filling of the injection mold cavity and the flow length respectively.Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089]; TBU in Zlin [IGA/FT/2016/010

Influence of Mixing Recycled Polycarbonate to Charpy Impact Properties at Increased Temperature

This article deals with influence of amount of mixing recycled material with virgin polycarbonate to impact properties. The aim is to perform an experiment in which the products of the studied polymer will be grinded to recycled material and then reprocessed into new specimens. These are then subjected to Charpy impact properties at increased temperatures. Several mixtures differing in the content of recycled material in virgin polycarbonate were prepared. One mixture was from pure recycled polycarbonate. The most used technology made testing samples for production of plastic products, which is injection moulding. Testing was conducted at increased temperatures 60 °C. This temperature was choose because many products are used at this temperatures. The impact of added recycled material to virgin polypropylene not significant for all impact properties. © 2018 The Authors, published by EDP Sciences.European Regional Development Fund under the project CEBIA:fech Instrumentation [CZ.1.0512.1.00/19.0376]; Ministr\, of Education, Youth and Sports of the Czech Republic within the National Sustainability Program [1,01303 (MSMT-7778/2014)]; Internal Grant Agency of TBIJ in Zlin [IGA/FT/2018/012

The Effect of Injection Molding on Physical Properties of EPDM Rubber

The paper a part of research aimed at the alternative of preparing test samples by injection molding. Such an alternative could bring more objective results in the field of testing samples produced in the same technology. The research is aimed at changing the preparation of rubber testing samples-replacing the standard method according to ISO 23529 by the injection method, especially with the use of rubber compounds for injection molding. This article compares and evaluates the selected physical properties (tensile strength and tear strength) of EPDM rubber injection molded samples with samples prepared by the standard method-cutting out of a compression molded plate. The results have shown that using the injection molded samples we will achieve more objective results mainly to determine the tear strength. In the case of tensile strength, the differences are not so significant. © 2018 The Authors, published by EDP Sciences.European Regional Development Fund under the project CEBIA-Tech Instrumentation [CZ.1.05/2.1.00/19.0376]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Program [L01303 (MSMT-7778/2014)]; Internal Grant Agency of TBU in Zlin [IGA/FT/2018/012

The influence of the injection molding on mechanical properties of EPDM rubber testing samples

The paper deals with the impact of the production process on mechanical properties (tensile strength and tear strength) of a standardized testing sample made of rubber compound based on ethylene propylene diene rubber produced by injection molding in comparison with a sample produced by classic preparation (cutting out a compression molded plate) according to the standard ISO 23529

Mechanical properties of injection molded and compression molded samples from nature-butadiene rubber

The aim of this paper is to show what extent there is an impact on the mechanical properties (tensile strength and tear strength) of a standardized testing sample made of rubber compound based on nature rubber and butadiene rubber produced by injection molding in comparison with a sample produced by classic preparation (cutting out a compression molded plate) according to the standard ISO 23529. For realization of this study it was necessary to design and produce an injection mold for all types testing samples. Subsequently, mechanical properties such as the tensile stress-strain and tear strenght of compression molded samples and injection molded samples were studied, compared and discussed.TBU in Zlin [IGA/FT/2016/010]; Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Programme [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089

Solving the issue of discriminant roughness of heterogeneous surfaces using elements of artificial intelligence

This work deals with investigative methods used for evaluation of the surface quality of selected metallic materials’ cutting plane that was created by CO2 and fiber laser machining. The surface quality expressed by Rz and Ra roughness parameters is examined depending on the sample material and the machining technology. The next part deals with the use of neural networks in the evaluation of measured data. In the last part, the measured data were statistically evaluated. Based on the conclusions of this analysis, the possibilities of using neural networks to determine the material of a given sample while knowing the roughness parameters were evaluated. The main goal of the presented paper is to demonstrate a solution capable of finding characteristic roughness values for heterogeneous surfaces. These surfaces are common in scientific as well as technical practice, and measuring their quality is challenging. This difficulty lies mainly in the fact that it is not possible to express their quality by a single statistical parameter. Thus, this paper's main aim is to demonstrate solutions using the cluster analysis methods and the hidden layer, solving the problem of discriminant and dividing the heterogeneous surface into individual zones that have characteristic parameters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.[IGA/FT/2021/006 TBU

The influence of the production process on mechanical properties of rubber testing samples

The article deals with the influence of production technology on mechanical properties of rubber testing samples. In practice, rubber testing samples are cut out from a compression molded sheet, also in case of testing of rubber compounds appointed for injection molding. However, the different way of the preparation of testing samples and the production itself may have a negative effect on the mechanical properties of the final product. Thus the article judges, to what extent the mechanical properties (tensile strength, extension, tear strength and microhardness) of testing samples from selected rubber materials are influenced by injection molding, and evaluates the possible divergence

Injection molding of rubber compound influenced by injection mold surface roughness

Delivery of polymer melts into the mold cavity is the most important stage of the injection molding process. This paper shows the influence of cavity surface roughness and technological parameters on the flow length of rubber into mold cavity. The fluidity of polymers is affected by many parameters (mold design, melt temperature, injection rate and pressures) and by the flow properties of polymers. Results of the experiments carried out with selected types of rubber compounds proved a minimal influence of surface roughness of the runners on the polymer melt flow. This considers excluding (if the conditions allow it) the very complex and expensive finishing operations from the technological process as the influence of the surface roughness on the flow characteristics does not seem to play as important role as was previously thought. Application of the measurement results may have significant influence on the production of shaping parts of the injection molds especially in changing the so far used processes and substituting them by less costly production processes which might increase the competitiveness of the tool producers and shorten the time between product plan and its implementation

Non-contact method of part surface scanning

Reverse engineering is now considered one of technologies for improving the quality of products and manufacturing equipment. It is a technology to provide business benefits in shortening the product development cycle. This paper shows that using two-dimensional laser CNC scanner with appropriate software can give acceptable results as more dimensional laser. Tool Digitalized Shape Editor of Software Catia V5R18 was applied for completing of scanning data at this experiment. These received data should be helpful and advantageous for using of 2D scanners. Ceramic coffee cup was used for the scanning to keep of author's hand writing