Applied Mechanics and Materials Vol. 827

Abstract: Shear properties and shear modulus of an advanced 3D multi-layer glass reinforced polyester thermoformed composite material to be used for manufacture of selected car body components were evaluated. The experimental methodology is described in detail and some aspects like effects of extensometer gauge length or minimum material macrostructure length unit on final results are analysed and discussed. Shear modulus values of the material are presented.

Abstract: Segmented moulds are special tools intended for tires with a complex groove pattern and demoulding is the final stage in tire manufacturing process during which some damage on tire surface can occur. The aim of this work is to carry how the amount of segments will influence the stress generated during mould opening on the rubber surface, as well as investigation of opening force required for the segment radial moving based on segment angles. The obtained results showed that for proposed symmetrical design of tire and material properties, the generated stresses are negligible and all proposed solutions may be used. If we do not consider the economical part, the optimal segment angle is 23° and the number of segments is 11.

Abstract: Fundamental knowledge of the mechanical properties of used materials are the basic preconditions for a successful construction of a final product. For seam as well as the reliability of its strength in some cases we need to know certainty when there will be the malfunction. In this study a spun of polyester thread were sewn on a material used for car seat cover. A single or multiaxial loading either static or dynamic has been used in the field of automotive textiles as well as for conventional materials. There is no standard method of measurement for the determination of dynamic strength of sewn seams and therefore it was necessary to construct a device that may measure the strength of seams under dynamic stress. It was carried out an experimental determination of the tensile strength under a static and shock loading for the textile part itself, then for the thread and also for them all together. A lot of very sophisticated numerical models of the individual materials structures in the world generally exist but considerably less is in this field taken into account the behavior of the whole.The aim of this work is with using the commercial software ANSYS create a contact numerical model that will be able to predict behavior of stitched seams and can be used instead of the classical experiments.

Abstract: This paper presents an experimental investigation of mechanical and impact properties of carbon and Kevlar-glass composites prepared from pre-impregnated materials. Namely, flexural performance in three-point bending at different temperatures is evaluated. Moreover, Charpy impact test and low-velocity impact test are also conducted for classification of impact properties and character of rupture. These all properties are important for material design of sport bike rims and many sport and other applications.

Abstract: Low velocity impact strength of the fabric reinforced geocomposite has investigated in this article. Various fabrics such as carbon and E-glass were considered for reinforcement in geopolymer matrix. The primary two parameters such as low velocity, impact damage modes are explained on the E-glass and carbon based fabric geocomposite. The onset mode of damage to failure mode is examined through C-scan analysis. The quality of the composite is observed using c-scan with acoustic vibration mode of sensor before and after impact test. Then the effect of fabric and matrix on the impact behaviour is discussed. Residual strength of the composite is measured to determine post impact behaviour. It has been observed that resistance properties of E-glass reinforced composite is better than carbon fabric reinforced composite.

Abstract: This thesis deals with the design of a joint for composite flexible elements using an integrated connection. For the verification of the selected layout, a wrapping loop was chosen as a simplified member, which was created on a special form designed for these samples. The material used was unidirectional fibreglass and epoxy resin. These samples were then compared using quasi-static tensile and compression tests. The tests were carried out with the Zwick-Roell Z050 machine. The resulting data of the experiment were then compared with the data obtained from numerical simulations using the finite element system Siemens NX 10 and SIMULIA Abaqus 6.13. 3D strength criteria Maximum stress and direct-mode strength criterion LaRC04 were used for evaluation.

Abstract: Composite materials are a regular part of many industries - aerospace, automotive, mechanical engineering. Lower weight and comparable in some ways even better mechanical properties, are the reason why composites progressively substitute traditional metal based material. The article describes the design of composite tub with metal reinforcement. Compares the theoretical and real output of sample produced from CF prepreg specially designed for absorbing the energy during crash impact. The results show that the sample due to its deformation is able to absorb some energy and become a material usable in structural applications.

Abstract: The interlaminar properties of a bond joint of stacked layers in a carbon fibre-reinforced composite with a thermoplastic matrix were evaluated under static loading. The un-precracked tension specimen with an external reinforcing layer was analysed in detail in the area of a bond joint. A detailed finite element method (FEM) analysis was performed to evaluate the influence of the bond joint shape on the interlaminar cohesive forces, which are simulated using the cohesive zone model (CZM). Simple lap and tapered joints were analysed. Continuum and shell elements were utilized in the FEM analysis, and the delamination results obtained using both solutions were compared to each other; however, no significant influence of the bond joint shape on the delamination onset was observed. The FEM analysis was supported using an experimental test on an un-precracked specimen made from prepreg with a carbon fibre fabric and a polyphenylene sulphide (PPS) matrix.

Abstract: Fiat 500 L tailgate was manufactured from innovative 3D functional textile – long glass fibre reinforced polyester thermoformed composite as a demonstrator within 3D Light Trans project of the EU 7^th Framework Programme. Unlike the second demonstrator, Bentley spare wheel well and battery case, the Fiat tailgate was characteristic by not negligible external loading and so, the strain and deformation behaviour had to be experimentally verified as the last step of the project implementation. Capabilities of the material for efficient manufacturing of different types of complex components were demonstrated. The tailgate provides an innovative high strength, low weight alternative to the nowadays customary metal parts manufactured with state-of-the-art technology. The experimental method and results are described in the paper.

Abstract: The multi-level method of stress-strain state analysis of ceramic parts is created. The algorithm for the designing of cutters with ceramic inserts is developed with the application of this method and it is successfully implemented in the manufacturing of cutter for groove cutting in tempered workpieces.