Core Powder Research Articles

Production of sustainable polyester composite building material using industrial waste plastic core, hemp fabric, and shrimp shell powder: Effect of quasi-isotropic fiber stacking and particle loading

This study investigates the mechanical, fatigue, and creep properties of commercial plywood (6 mm) alternative polyester composite prepared using waste plastic core, hemp fiber, and shrimp shell powder. The primary aim of this research was to develop an exact replacement for plywood building material and study the effect of fiber stacking order as well as the volume fraction of shrimp shell biopolymer on load-bearing and time-dependent properties. Composites' distinct quasi-isotropic stacking orders with varying hemp fiber angles and shrimp filler contents of 0%, 1.0%, and 3.0% were prepared via compression molding and tested based on ASTM standards. Results revealed that the “D” stacking order {(−45/45) + (−30/60) + WPC + (−60/30) + (−45/45)} composite consistently outperformed others, exhibiting superior mechanical strength. Specifically, the D2 composite exhibited elevated strength, including a tensile strength of 168 MPa, flexural strength of 199 MPa, compression strength of 181 MPa, impact energy of 6.23 J, interlaminar shear strength of 25.9 MPa, and v-notch rail shear of 19.7 MPa. The addition of shrimp filler, rich in hydroxyl groups, enhanced intermolecular interactions, contributing to a resilient network and improved fatigue resistance. Moreover, the creep resistance was notably influenced by the quasi-isotropic arrangement, with the “D” designation showcasing optimal performance. Microscopic analysis revealed the critical role of shrimp shell content in promoting cohesion and interlocking fiber structures. The findings underscore the intricate synergy between stacking angles; filler composition and content in achieving robust and eco-friendly polyester composite building material to replace the termite, weather, and water affect commercial plywood.

Physicochemical properties and pork preservation effects of lotus seed drill core powder starch-based active packaging films

Lotus seed drill core powder starch (LCPS)-based active packaging films incorporated with cellulose nanocrystals (CNC) and grapefruit essential oil-corn nanostarch Pickering emulsion (ECPE) were characterized, and their pork preservation effects were investigated in this study. In contrast with corn, potato and rice starches, LCPS showed higher amylose content, elliptical and circular shape with more uniform size distribution. Furthermore, LCPS film exhibited lower light transmittance, stronger tensile strength, and smaller elongation at break compared to the other starch films. Then, the LCPS film containing 4 % CNC and 9 % ECPE was fabricated which had stronger mechanical properties, lower water vapor permeability and oxygen transmission rate, and denser network structure. FTIR and XRD analyses also confirmed that CNC and ECPE were successfully implanted into the LCPS matrix without damaging the crystalline structure of LCPS. Herein, the LCPS/CNC/ECPE film exerted potential antibacterial activity against Escherichia coli and Staphylococcus aureus. Besides, packaging with this composite film significantly preserved the pork during cold storage via decreasing its juice loss rate, pH value, total number of colonies, total volatile base nitrogen and thiobarbituric acid reactive substance values. The present study will provide a theoretical basis for the application of LCPS as new biodegradable active films.

Effect of pineapple core powder on white finger millet vegan probiotic beverage: Nutrition, sensory and storage

The present study aims to develop, optimize, and evaluate the effective incorporation of pineapple core powder (PCP) in plant-based probiotic beverages using Lactocaseibacillus rhamnosus (LGG). The optimization was carried out using pH, viscosity, and LGG viable load as response variables in the d-optimal mixer design. In optimized products, the changes in pH, titratable acidity (TA), and LGG viable load are observed during fermentation and storage conditions. The optimum condition for developing PCP-added white finger millet probiotic beverage (PAMPB) was 14:5:2:2 for white finger millet, sugar, PCP, and LGG inoculums, respectively. A PAMPB provided a higher LGG viable load of 11.34 log (CFU/mL) within 6 h of fermentation time. The PCP effectively increases the physiochemical properties like total phenolic count (17.64 mg GAE/g), total antioxidant activity, total flavonoid count (8.59 mg QE/g), and water holding capacity (41.52 %) of the PAMPB. In addition, the different sugar profiles and new pineapple aroma compounds like ethyl hexanoate and methyl hexanoate are identified in PAMPB. During the storage of PAMPB at 4⁰C for 21 days, the reduction in LGG viable count was observed from 11.54 to 9.39 log (CFU/mL). Incorporating PCP in millet beverages provides a positive result by increasing nutritional quality.

New Approach for Manufacturing Ti–6Al–4V+40%TiC Metal-Matrix Composites by 3D Printing Using Conic Electron Beam and Cored Wire. Pt. 2: Layered MMC/Alloy Materials, Their Main Characteristics, and Possible Application as Ballistic Resistant Materials

Bilayer samples comprised of hard metal-matrix composite top layer and ductile 10 mm Ti–6Al–4V plate are produced with 3D printing by conical electron-beam method using specially prepared core (powder) wire that allows forming hard top layer of metal-matrix (Ti–6Al–4V) composite (MMC) reinforced by means of fine TiC particles with thickness up to 4 mm. Ballistic tests performed with 7.62×51 AP ammunition show a good ballistic resistance of this protective structure, i.e., it is not perforated. Only minor penetration and partial fracture are occurred exclusively in the surface MMC layer. Either no traces of plastic deformation are found at the boundary with the base layer or inside it that indicates that the MMC layer absorbs the entire impact energy of the projectile. Based on studies of the fine structure and texture of the interface between the layers, a reasonable assumption is made that wavy geometry of MMC layer provides additional deflection and scattering of stress waves generated during impact. Comparing the results of ballistic tests of various metallic materials, it is concluded that the 3D-printed bilayer material consisting of the upper Ti–6Al–4V + 40% TiC layer and the base Ti–6Al–4V layer has an undeniable advantage in ballistic performance when it is tested with cartridges of this type.

Enhancement of cation exchange and glucose binding capacity, flavonoids release and antioxidant capacity of Tartary buckwheat powder with ultrafine grinding

The objective of this paper was to study the effects of ultrafine grinding on the cation exchange capacity, glucose binding capacity and in vitro digestion characteristics of Tartary buckwheat powder. The results showed that the cation exchange ability and glucose binding strength of Tartary buckwheat powder, Tartary buckwheat bran powder and Tartary buckwheat core powder increased significantly with the increase of crushing frequency (20, 40 and 60 Hz), and the Tartary buckwheat bran powder was the highest. The results of in vitro digestion showed that ultrafine grinding improved the flavonoid release and antioxidant activity of Tartary buckwheat bran powder in the in vitro digestion process. The correlation analysis indicated that the amount of flavonoids released in digestive fluid was significantly related to antioxidant activity. This study may provide a theoretical basis for improving the physicochemical properties and functions of Tartary buckwheat by ultrafine grinding technology.

Adsorption of Pb (II) Ions in Water with Natural Kenaf Beads

The purpose of this research is to study plant-based kenaf adsorbents on the adsorption of polluted Pb (II) in aqueous solutions. CHT and KNF core powder were added to the sodium alginate solution and stirred homogeneously. The blend solution was dripped into calcium chloride to form smooth magnetic KNF-CHT-ALG beads. The functional group presence in the beads and percentage adsorption of the heavy metals were checked using Fourier Transform Infrared Spectroscopy (FTIR) and Inductively Coupling Method analyses, respectively. It was found that the surface morphology of kenaf core was rougher than that of kenaf fibre, with the presence of a larger amount of micropores as observed in the FESEM analysis. In addition, the FTIR pattern of the KNF-CHT-ALG beads had shown the existence of functional groups such as hydroxyl and carboxyl, which could attract more positively charged heavy metals. The ICP analysis confirmed the successful 95% adsorption of the heavy metals. Kenaf is an abundant crop available in Malaysia that may reduce the production cost of the adsorbents. The significant outcomes of this study would be its contribution to minimising the dependency on the chemical adsorbent and to accelerating the removal process of heavy metals in real water bodies. Thus, this study aims to create a more sustainable future, especially by reaching SDG 6: Clean Water and Sanitation.

Effect of biowaste and construction waste additives on mechanical dewaterability of lake sediment for brick production

ABSTRACT Nowadays, when the zero-waste strategy is an inevitable component of the circular economy, the reuse of waste, including dredged sludges, has drawn the attention of many researchers. This study evaluated four kinds of bio-wastes (corn core powder, rice husk powder, sugarcane bagasse powder, and peanut shell powders) and two kinds of construction wastes (autoclaved aerated concrete-AAC and pavement stone) in enhancing the dewaterability of dredged sludge from the lake, in which the sludges would then be reused for brick production. The results showed that the moisture contents decreased from 62 ± 0.14% to 57 ± 1.89% after mixing and then to 35 ± 8.31% after compressing for the construction waste-blended sludge. Among the bio-wastes, the sugarcane bagasse additive performed the best at a mixing ratio of 1:3 by weight and rice husk powder worked best at a mixing ratio of 1:5 by weight. The organic matter was increased up to 80% when the bio-wastes were added, while it was decreased to 5% for the case of construction wastes. The optimum percentage of sludge in the mixture to meet all the oxide contents in the brick and energy saving shall be about 30%. The results have revealed a potentially green route for brick production with lake sediment and bio-waste/construction wastes. Implications: It is the first time the reuse of agro-wastes/construction waste was evaluated to mix with lake sediment to partly replace clay for brick production; Among the bio-wastes, the sugarcane bagasse additive performed the best at a mixing ratio of 1:3 by weight; Moisture contents decreased from 62 ± 0.14% to 57 ± 1.89% after mixing and then to 35 ± 8.31% after compressing for the blended sludge; The optimum percentage of mixed sludge, possibly replaced the clay in brick production, considering oxide contents and energy saving shall be up to 30%.

Reuse of agrowastes for dewatering enhancement of sewer sediments for brick production

With the increasing wastewater generation from domestic and industrial activities due to the rapid economic development, the generation of sludge, in particular dredged sludge from municipal sewer system, has been an issue in developing countries. This study evaluated the enhancement of sewer’s sludge dewatering via mixingthe sludgewith different agro-wastes, including corn core powder, rice husk powder, bagasse powder and peanut shell powder. The addition of these agro-waste powders helped decrease the sludge’s moisture contents up to 17% while increase the organic matters nearly to 40% after mixing with the ratio of agro-wastes and sludge of 1:3. Statistical analysis revealed the impacts of both additive types and mixing ratio on moisture content reduction. Among the four types of agro-waste, rice husk was shown to be the best additive to dredged sludges with highest reduction of heavy metal concentration and moisture content. The addition of agro-waste powders to enhance the dewatering of sludges is promising in the context of promoting waste reuse and energy saving.

Acceptability of Green Jackfruit (Artocarpus heterophyllus) Rind and Core as an Alternative to Flour in Noodles

Jackfruit (Artocarpus heterophyllus) is also known locally as "nangka" or "langka." After consuming the edible portion of the unripe fruit, the rind and core were discarded as waste. This research aimed to look into the functional properties of green jackfruit rind and core flours to provide helpful information for their use as a flour substitute in noodles and significantly reduce food waste. Having tested the sensory qualities of green jackfruit rind and core powder (JRCF), the three formulations were made by substituting all-purpose flour with 33%, 50%, and 67% green jackfruit rind and core flour. The physicochemical and proximate composition of the most acceptable treatment, a mix of 33% JRCF and 67% APF was analyzed. The noodles made from green jackfruit rind and core flour had a moisture content of 12.05 %, 1.40 % crude ash, 17.56 % crude fat, 6.05 % crude fiber, 4.42 % crude protein, and a pH of 5.63. It was observed that since young green jackfruit contains more acid and is more fibrous, it is preferable to use matured jackfruit. Furthermore, to make it more aesthetically acceptable to consumers, the produced jackfruit rind and core noodles must also enhance their sensory attributes in terms of color and texture.

Phytosterol of lotus seed core powder alleviates hypercholesterolemia by regulating gut microbiota in high-cholesterol diet-induced C57BL/6J mice

The present study aimed to investigate the regulatory mechanisms of lotus seed core powder phytosterol extract (LSP-PE) on hypercholesterolemia and intestinal microbiota in high-cholesterol diet (HCD)-induced C57BL/6 J mice. Gavage with LSP-PE reduced levels of serum total cholesterol (TC), ratio of low-density lipoprotein cholesterol (LDL-C) to high-density lipoprotein cholesterol (HDL-C), hepatic TC, hepatic triglyceride (TG), hepatic LDL-C, hepatic very low-density lipoprotein (VLDL), fecal TC and fecal total bile acid (TBA), while augmented hepatic HDL-C content. In contrast with HCD group, high-dose LSP triggered significant diminutions of serum ALT, serum AST, hepatic ALT and hepatic AST levels in HCD-fed mice, which were 16.49, 28.94, 43.42, and 44.47%, respectively, thus remarkably ameliorating the pathological changes of liver and small intestine. In-depth genetic research found that LSP was effective in down-regulating the expression of cholesterol metabolism related genes including Niemannpick C1-like protein 1 (NPC1L1), acyl-coA cholesterol acyl-transferase 2 (ACAT2), microsomal triglyceride transporter (MTP) and ATP binding cassette subfamily G member 5 (ABCG5). Moreover, LSP-PE could restore the disorder of intestinal flora via augmenting the Actinobacteria abundance as well as decreasing the Firmicutes/Bacteroidetes ratio and abundances of Proteobacteria and Verrucomicrobia to regulate cholesterol metabolism-related genes. In summary, LSP-PE possessed excellent cholesterol-lowering activity by positively regulating the gut microbiota and the expression levels of genes related to cholesterol absorption and metabolism. Therefore, this work suggested LSP phytosterol as a potential supplement to alleviate the symptoms of hypercholesterolemia.

Cabbage Core Powder as a New Food Material for Paste Preparation with "Nata Puree".

Cabbage core (CC) is regarded as a waste part of the vegetable, despite being edible and containing various nutritional and functional compounds. We investigated the properties of CC powder with particle sizes < 1 mm as a new food material. CC powder was more resistant to structural deformation than leaf-derived powder, particularly CC powder with particles ≥ 0.3 mm in size. To examine the application of CC powder in 3D printed foods, we investigated the effects of "nata puree," a disintegrated nata de coco made with tamarind seed gum (NPTG), on paste made with CC powder. NPTG promoted stable binding of paste made using CC powder, which was successfully extruded using a syringe to form a bar with a granular structure. Thus, CC powder possesses unique textural/structural properties for its application in next-generation foods.

Fabrication and characterization of Sn@Viod@Ceramic phase change macrocapsules for medium-temperature thermal storage

Metallic phase change material (PCM) has great application prospects in the field of medium-temperature thermal storage. Macro-encapsulated PCMs with larger core-shell volume ratio and higher heat storage density can solve the millimeter level packaging problem of metallic PCM. However, it is easy to break for the macrocapsules after thermal cycling due to the large volume expansion during phase change. To solve this problem, a novel metal phase change macrocapsule with a thermal expansion void is prepared successfully with Sn powders as PCM core and ceramic powders (Al2O3, AlN, Kaolin or SiC, respectively) as shell raw materials. The voids are introduced by the packing spaces of raw Sn powders as core balls. The results show that the void can accommodate volume expansion of the metal PCM during heat storage and the four kinds of ceramic shells show high corrosion resistance and high compatibility. Thermal analysis indicates that the melting temperature of core (Sn PCM) after 50 cycles is 232.2 °C and the latent heats are 58.0 J/g and 58.3 J/g for melting and crystallization, respectively. Thermal tests confirm that the macrocapsules have excellent oxidation resistance, thermal stability and cycle durability in the practical working temperature range (about 100–300 °C).

Effect of Helium Plasma Exposure on Wettability and Shear Bond Strength between the Zirconia Core and Feldspathic Veneering Ceramic: An In Vitro Study

Introduction The present study aimed to evaluate the effect of helium plasma treatment on the wettability of zirconia surface and on the shear bond strength between the dental zirconia core and feldspathic veneering ceramic. Methods 128 zirconia specimens were prepared, polished, and then divided into four groups: control, Zr, FC, and Zr/FC. In Zr and Zr/FC groups, the zirconia blocks were treated by helium plasma for 60 s. In FC and Zr/FC, the feldspathic ceramic powder received 60 s of plasma treatment. Then, the feldspathic powder was applied on the zirconia blocks. Half of the specimens in each group were sintered in a tube furnace, and the contact angle between the zirconia core and feldspathic ceramic was measured at different time intervals. The other half were sintered in a ceramic furnace and then subjected to thermocycling. The shear bond strength was measured using a universal testing machine. The failure mode was assessed using a stereomicroscope. Data were analyzed by one-way ANOVA test, and the statistical significance was considered less than 0.05. Results There was no significant difference in the mean contact angle and the shear bond strength values of the experimental groups (P > 0.05). The mean contact angle decreased significantly in all groups over time (P < 0.001). The modes of failure were predominantly mixed in all groups. Conclusion The helium plasma applied on either dental zirconia core or feldspathic ceramic powder could not improve the zirconia surface wettability and the shear bond strength between the two ceramics.

Experimental investigation on the mechanism of low permeability natural gas extraction accompanied by carbon dioxide sequestration

The injection of CO2 into natural gas reservoir is regarded can increase natural gas recovery accompanied with CO2 sequestration. In this work, we first demonstrated that the gas adsorption ability in the sampled plunger low permeability sandstone core was only about 1/10 of that in the core powders, the former was more representative for use. The existence of bound water substantially weakened the gas adsorption in the core. The CO2 diffusion coefficients in low permeability cores were in the order of 10−8-10−9 m2/s, which increased with decreasing pressure but dramatically decreased with the existence of bound water. Last, long core experiments for natural gas recovery through CO2 flooding showed that the CO2 injection substantially increased the natural gas recovery ratio R. And we for the first time demonstrated that due to the higher CO2 density than that of natural gas through experiments, the CO2 injection at the relative low position showed higher R than that at the high injection position. And with the highest CO2 sequestration amount (M) reached 64.36 kg/m3. The injection of CO2 into low permeability natural gas reservoir to realize both natural gas recovery and CO2 sequestration are tested feasible and effective.

Phytosterol of Lotus Seed Core Powder Alleviates Hypercholesterolemia by Regulating Gut Microbiota and Cholesterol Metabolism in High-Cholesterol Diet-Induced C57BL/6J Mice

Phytosterol of Lotus Seed Core Powder Alleviates Hypercholesterolemia by Regulating Gut Microbiota and Cholesterol Metabolism in High-Cholesterol Diet-Induced C57BL/6J Mice

Corrosion Behavior of the CoNiCrAlY-Al2O3 Composite Coating Based on Core-Shell Structured Powder Design.

The oxidation of the metal powder during the thermal spraying process usually leads to significant deterioration of the microstructure and performance of the coating. In order to isolate the metal powder from oxygen during the spraying process, the CoNiCrAlY-Al2O3 core-shell structured powder with Al2O3 as the shell was designed in this study. The influence of the core-shell structured powder on the microstructure and corrosion resistance of the HVOF coating has been studied in detail. The results show that the temperature field of the molten CoNiCrAlY powder during the spraying process is significantly changed by the Al2O3 shell. The poor deformability of the CoNiCrAlY-Al2O3 droplets leads to an increase in the porosity and unmelted particles of the coating. In addition, the significant difference is that the coating also maintains a high content of β-NiAl phase. The lower oxide content in the CoNiCrAlY-Al2O3 coating indicates that the core-shell structured powder significantly inhibits the oxidation of the CoNiCrAlY core powder during the spraying process. The CoNiCrAlY-Al2O3 coating exhibits high corrosion potential, passive film resistance, charge transfer resistance, and low corrosion current density in 3.5 wt.% NaCl solution, indicating that the coating has excellent corrosion resistance.

Sol–Gel Encapsulation of ZnAl Alloy Powder with Alumina Shell

Additive manufacturing (AM), for example, directed energy deposition (DED), may allow the processing of self-healing metal–matrix composites (SHMMCs). The sealing of cracks in these SHMMCs would be achieved via the melting of micro-encapsulated low melting point particulates (LMPPs), incorporated into the material during AM, by heat treatment of the part during service. Zn-Al alloys are good candidates to serve as LMPPs, for example, when the matrix of the MMC is made of an aluminum alloy. However, such powders should first be encapsulated by a thermal and diffusion barrier. Here, we propose a sol–gel process for encapsulation of a custom-made ZA-8 (Zn92Al8, wt.%) core powder in a ceramic alumina (Al2O3) shell. We first modify the surface of the ZA-8 powder with (12-phosphonododecyl)phosphonic acid (Di-PA) hydrophobic self-assembled monolayer (SAM) in order to prevent extensive hydrogen evolution and formation of non-uniform and porous oxide/hydroxide surface layers during the sol–gel process. Calcination for 1 h at 500 °C is found to be insufficient for complete boehmite-to-γ(Al2O3) phase transformation. Thermal stability tests in an air-atmosphere furnace at 600 °C for 1 h result in melting, distortion, and sintering into a brittle sponge (aggregate) of the as-atomized powder. In contrast, the core/shell powder is not sintered and preserves its spherical morphology, with no apparent “leaks” of the ZA-8 core alloy out of the ceramic encapsulation.

Influence of Thermal Annealing on the Sinterability of Different Grades of Polylactide Microspheres Dedicated for Laser Sintering.

We present a comparison of the influence of the conditioning temperature of microspheres made of medical grade poly(L-lactide) (PLLA) and polylactide with 4 wt % of D-lactide content (PLA) on the thermal and structural properties. The microspheres were fabricated using the solid-in-oil-in-water method for applications in additive manufacturing. The microspheres were annealed below the glass transition temperature (Tg), above Tg but below the onset of cold crystallization, and at two temperatures selected from the range of cold crystallization corresponding to the crystallization of the α’ and α form of poly(L-lactide), i.e., at 40, 70, 90, and 120 °C, in order to verify the influence of the conditioning temperature on the sinterability of the microspheres set as the sintering window (SW). Based on differential scanning calorimetry measurements, the SWs of the microspheres were evaluated with consideration of the existence of cold crystallization and reorganization of crystal polymorphs. The results indicated that the conditioning temperature influenced the availability and range of the SWs depending on the D-lactide presence. We postulate the need for an individual approach for polylactide powders in determining the SW as a temperature range free of any thermal events. We also characterized other core powder characteristics, such as the residual solvent content, morphology, particle size distribution, powder flowability, and thermal conductivity, as key properties for successful laser sintering. The microspheres were close to spheres, and the size of the microspheres was below 100 µm. The residual solvent content decreased with the increase of the annealing temperature. The thermal conductivities were 0.073 and 0.064 W/mK for PLA and PLLA microspheres, respectively, and this depended on the spherical shape of the microspheres. The wide angle X-ray diffraction (WAXD) studies proved that an increase in the conditioning temperature caused a slight increase in the crystallinity degree for PLLA microspheres and a clear increase in crystallization for the PLA microspheres.

Fiber Enrichment in Noodles using Banana Pseudo-stem (Musa paradaisiaca)

Background: Despite the fondness for noodles, consumers in India hold the notion that noodles are being made from maida which is seen as product with low fiber. Hence an attempt was made to develop fiber enriched noodles by incorporating banana pseudo-stem tender core powder (BPP) as a fiber source. Methods: BPP was incorporated at different levels viz., 5, 10 and 15% in which 5% was found to be the best based on cooking characteristics and sensory evaluation. The noodles thus prepared were packed in flexible polyethylene pouches and stored at room temperature and were further analyzed for physicochemical, cooking, sensory and colour characteristics at regular intervals of 60 days till 180 days of storage. Result: All the analysis showed the non-significant difference during the storage period stating that the product is good till 180 days of storage. The dietary fiber was found to increase from 3.35 to 4.74% and in vitro method of glycemic index (GI) analysis showed that the fiber noodle was a low GI food when compared to the medium GI of control. The MUFA and PUFA content of BPP noodles were increased when compared to control.

Investigation of the repair method alternatives for porous pet structures

Wind turbine systems, which are one of the renewable energy sources, convert wind energy into electrical energy, cover the blade components those are produced as sandwich composite materials for the last half century. TPI Composite, a wind turbine blade manufacturer in the renewable energy sector, has an important position in the field.&#x0D; In the sandwich composite structures, the core material providing the force transfer between the face sheets and plays an important role in increasing the bending stiffness of the sandwich structure. This non-structural material component, which is thicker but lightweight, porous and low density, is used in the wind turbine blade subcomponents.&#x0D; The main shear web (MSW), which is a subcomponent of the wind turbine composite blade and provides the mechanical strength between the two skins (suction side &amp; pressure side) of the blade, is a composite structure with a parabolic geometric distribution produced by vacuum infusion method. Due to the geometrical shape and placement of various shaped cores of the MSW, there might occur some gaps between the foam cores placed in the MSW during the production due to vacuum. In this study, compression and bending behaviors of the foam core were investigated. Specimens with dimensions of 50x50x30 mm were prepared vacuum infusion method of core structures whose top and bottom skins covered with glass-reinforced epoxy composite face sheets. Then, some specimens were filled with core powder and core strip respectively to represent the repair method. The test specimens were subjected to flatwise compression and three-point bending tests. The performances of different gap filling repair methods were compared, and the changing performance of the damaged core specimens were investigated against specimens without any defect. To evaluate the alternative repair methods that could be applied during the production of MSW, gap filling repair alternatives, repair applicability limits and changing of the mechanical properties compared to virgin specimens were investigated for the sandwich structures with E-glass reinforced/epoxy face sheets and PET foam core.