Papers by Keyword: Lamination

Abstract: Industrialization and the increase in population in the world have led to a great increase in the amount of solid waste. Plastic and textile wastes have an important share among the solid wastes, which include many different waste groups. While the increase in disposable products increases the amount of plastic waste, the understanding of fast fashion is among the most important reasons for the increase in textile waste. In this study, cotton based woven textile wastes (2^nd quality denim fabric) are laminated with plastic packaging wastes (high density polyethylene (HDPE) and low density polyethylene (LDPE) water bottle caps) in various sequences and thickness, areal density and fiber weight ratio values of these structures are examined. In addition, the impact properties of the produced laminated composite structures are analyzed via drop-weight impact testing machine. The results show that the increase in the number of fabric layers contributes positively to the energy absorption rate thus the samples including two layers of fabrics and one layer of either LDPE or HDPE plastic sheet have the highest maximum loads and absorbed energy values. In addition, it is also seen that HDPE lamination results in higher absorbed energy values compared to LDPE lamination.

Abstract: The paper analyzes the structure of coal beds. It is noted that coal beds belong to laminar massifs with characteristic oriented structure and pronounced anisotropy of strength properties, and include rock layers and consolidated hard inclusions. The quality criteria of the coal loosening process are highlighted. A selective method of separating coal from a massif by cutting along weakened surfaces is proposed as an alternative to the existing combine technology with continuous cutting of a massif from the surface.

Abstract: In this study, chitin-cellulose films (CC) and nanocomposite (NC) films were successfully laminated to thermoplastic starch (TPS). These were prepared using adhesive, controlled heated compression, and heated compression with adhesive. Lamination was investigated by utilizing direct tensile adhesion strength test to acquire the adhesion strength between the two layers. The highest adhesion strength of 0.502±0.036 MPa resulted for CC/TPS. Combination of failure at the interface and substrate was observed for most CC/TPS laminates. FTIR spectra indicated presence of -NH groups from chitin and -OH groups from starch and cellulose that could improve interfacial adhesion by hydrogen bonding. Scanning Electron Micrographs (SEM) showed a rough surface of chitin-cellulose films, and the clear continuity of CC film with TPS. An increase in modulus from from 0.342 ± 0.020 MPa for TPS to 1.059 ± 0.162 for CC/TPS and 0.939 ± 0.143 MPa for NC/TPS.

Abstract: Energy efficiency of buildings is one of the basic requirements of current architectural engineering. The new recast of the Energy Performance of Buildings Directive (EPBD) calls for all new buildings to be nearly zero energy buildings by the end of 2020. To achieve this target is quite challenging. The article deals with the design of a shading system, which consists of lamination made from photovoltaic modules and phase change materials. The lamination is composed of thin but durable photovoltaic modules, which are located on the profile formed from aluminum in which the phase change material is mounted. The shading system is a part of the building facade from the exterior side. In this article there are presented results of simulation of a single zone which was set with a shading system using two different phase change materials.

Abstract: For advanced ceramic composites, affordable manufacturing is still the most essential shortcoming with respect to successful commercial use. This holds particularly for components made out of composites with complex hierarchical structures and high demands of mechanical performance and reliability at the same time, e.g. fiber-reinforced ceramic matrix composites (FRCMCs). Therefore, a new processing route is presented here, which is based on the lamination of thermoplastic prepregs. This route allows not only affordable manufacturing, but also advanced mechanical reliability. Powder metallurgy techniques are combined here with concepts from the prepreg technology in a route consisting of the following steps (a) manufacturing of 2 D prepregs using commercial fiber fabrics which are infiltrated with compounds of ceramic particles embedded in an organic matrix, (b) followed by respective stacking and joining, (c) burn out of the organic matrix and (d) sintering to consolidate the matrix. Composites consisting of a porous Al₂O₃/ZrO₂ matrix, reinforced by 8 layers of NextelTM 610 fiber fabric exhibit a bending strength of ~440 MPa, with graceful failure behavior, e.g. a stepwise stress reduction after peak nominal stress. The fracture of these composites is controlled by a series of interfacial delamination events, which enhance energy dissipation during failure.

Abstract: For achieving high-temperature resistance and a broadband of microwave transmission, ceramic metamaterials consisting of fused silica ceramic substrates and electrically conductive networks/ arrays are desirable. A new strategy of fabricating the fused silica metamaterials is to combine the low temperature co-fired ceramic (LTCC) technique with a method of ceramic joining via green tapes. The important part of the new strategy lies in the preparation of suitable green tapes that are co-firable with a conductive silver-based film/strip and have a strong affinity to the fused silica substrates. Therefore, in this paper, three green tape materials were prepared and intensively characterised using scanning electron microscopy, x-ray diffraction, dilatometry, dielectric measurement, etc. It was found that the tape materials were based on dielectric glasses and crystalline phases of major eulytite and minor cristobalite, leading to rather low levels of dielectric constant (<6) and loss tangent (in the order of 10^-3). The three tape materials also had different levels of thermal expansion coefficients, co-firability with a conductive silver-based paste, and bondability to the fused silica substrates. These findings suggest that one can achieve desirable ceramic matematerials with well-controlled shapes and dimensions of the condutive networks/arrays after properly laminating the green tapes between the fused silica substrates.

Abstract: Sandwich structural composites (CFRP/ABS/CFRP) of inexpensive acrylonitrile butadiene styrene (ABS) cores (2.0 mm thickness) between carbon fiber reinforced epoxy (CFRP) laminate plies (2.5 mm thickness) were suggested and prepared, since the materials cost of ABS resin was about 8% that of CFRP. Although Young’s modulus of CFRP/ABS/ CFRP is slightly smaller than that of CFRP, Charpy impact value (a_uc) of the CFRP/ABS/CFRP approximately corresponded to that of CFRP composite. Furthermore, applying homogeneous low voltage electron beam irradiation (HLEBI) to both side surfaces improved the a_uc of CFRP/ABS/CFRP. Since the irradiated depth estimated is about 119 ± 23 μm, the irradiation effects mostly acted within the CFRP sheet. The Charpy impact value (a_uc) of CFRP/ABS/CFRP at mid-fracture probability (P_f ) after irradiation at 0.30 MGy (kJg^_1) was approximately 25 % higher than that before treatment. It was approximately equal to that for irradiated CFRP and was also about 20% higher than that of the CFRP before treatment. Although the use of ABS resin as the core reduced other mechanical properties of tensile and bending, the materials cost of CFRP/ABS/CFRP was approximately 25 % that of CFRP. Thus, the sandwich structural composites of CFRP/ABS/CFRP could be utilized for daily articles.

Abstract: In this paper, green ceramic tapes are joined together by adhesive based lamination technique. The effects of adhesive concentration, pressure on the lamination and sintering temperature on the laminate are mainly discussed. The parameters are also optimized. It was shown that the effect of adhesive concentration and pressure on the lamination is obvious and the effect of sintering temperature is not big. 10 layers of cordierite tapes can be laminated under 2MPa with a dwell time of 3min with PVA by adhesive based lamination. The adhesive based lamination can be used to be an alternative of thermo-compressive lamination.

Abstract: This thesis deals with the assessment of the effect of the process of lamination microporous nanofiber membrane on the overall evaporative resistance of the two-layer laminate. For most multi-layer materials, lamination process is due to the deterioration of some properties of the whole laminate, particularly to the increase of the evaporative resistance. The authors of this thesis investigate the effect of the lamination primarily on the evaporative resistance of two-layer laminates. The study deals with the relations of volume porosity with the values of the evaporative resistance of the laminate too. In this thesis are both measured the separated layers of selected materials (upper material and the membrane), then the surface materials with the coated lamination points and subsequently created two-layer laminates.

Abstract: In this paper, the interlaminar shear strength properties of laminated binderless bamboo composites is described. The binderless bamboo composites were prepared by hot-pressing of steam-exploded Moso bamboo stripes. In order to explore the effect of node section on the mechanical properties of the laminated binderless bamboo composites, the node section was flattened by shaving the nodes off. The result of our experiment clearly shows that the shear strength of the laminated binderless bamboo composites increased by flattening of the node section.