Mechanical properties comparison of PLA, tough PLA and PC 3D printed materials with infill structure – Influence of infill pattern on tensile mechanical properties

One of the advantages provided by fused deposition modelling (FDM) 3D printing technology is the manufacturing of product materials with infill structure, which provides advantages such as reduced production time, product weight and even the final price. In this paper, the tensile mechanical properties, tensile strength and elastic modulus, of PLA, Tough PLA and PC FDM 3D printed materials with the infill structure were analysed and compared. Also, the influence of infill pattern on tensile properties was analysed. Material testing were performed according to ISO 527-2 standard. All results are statistically analysed and results showed that infill pattern have influence on tensile mechanical properties for all three materials.

Optimization of Extrusion Process Using Response Surface Methodology for Producing Squid and Millet Based Extrudate

The squid is underutilized seafood than finfish and shellfishes in domestic consumption and millet is also an underutilized food grain. This study aimed to produce squid and millet- based extrudate under the optimized process parameters using Response Surface Methodology (RSM). The effects of process parameters such as heater 1 temperature (55°C, 60°C and 65°C), heater 2 temperature (120°C, 125°C and130°C), screw speed (250 rpm, 275 rpm and 300 rpm), and inclusion of squid powder (3%, 4%, 5%, 6% and 7%) were tested for responses like bulk density, expansion ratio and fifty product weight in RSM. All process parameters tested had significant (P<0.05) impact on responses. The optimized parameters were found to be 64.10°C of heater 1 temperature, 129.98°C of heater 2 temperature, screw speed of 317.87 rpm, and 6.56% of inclusion of squid powder.

Application of the K-Means Algorithm to Segmentation of Consumer Interest in Silver Craft "Kreasi Slaka Bali"

Kreasi Slaka Bali is a company engaged in the silver handicraft sector. Each stage of the process is still done manually, starting from material preparation, handmade work, until making the packaging for delivery. Certainly, this requires more time to be able to produce an item of the same quality in each production. The need for extra time and business in product manufacturing, the company needs a marketing strategy that can be seen from consumer interest in the product. So this research discusses consumer interest based on transaction data by forming clusters based on purchases amount with other attributes, namely the product price, product size, product weight, and level of difficulty. The data used is transaction data for 2 transactions in 2019. The algorithm used is K-Means with the Elbow Method to determine the number of clusters. There are clusters of k = 5 with the cluster that has the most data in the first cluster (k = 0) with a total purchase of 193 products with an average price of US $ 69,554688.

Study of an Online Monitoring Adaptive System for an Injection Molding Process Based on a Nozzle Pressure Curve

Injection molding is a popular process for the mass production of polymer products, but due to the characteristics of the injection process, there are many factors that will affect the product quality during the long fabrication processes. In this study, an adaptive adjustment system was developed by C++ programming to adjust the V/P switchover point and injection speed during the injection molding process in order to minimize the variation of the product weight. Based on a series of preliminary experiments, it was found that the viscosity index and peak pressure had a strong correlation with the weight of the injection-molded parts. Therefore, the viscosity index and peak pressure are used to guide the adjustment in the presented control system, and only one nozzle pressure sensor is used in the system. The results of the preliminary experiments indicate that the reduction of the packing time and setting enough clamping force can decrease the variation of the injected weight without turning on the adaptive control system; meanwhile, the master pressure curve obtained from the preliminary experiment was used as the control target of the system. With this system, the variation of the product weight and coefficient of variation (CV) of the product weight can be decreased to 0.21 and 0.05%, respectively.

Active Cardboard Packaging With Encapsulated Essential Oils for Enhancing the Shelf Life of Fruit and Vegetables

The quality loss of fruit and vegetables should be minimized to reduce food waste during retail. In that sense, sustainable and effective post-harvest techniques/technologies are needed, showing active packaging including encapsulated essential oils a high potential. In that sense, we studied the effect of different sized active packages (including β-cyclodextrin-EOs inclusion complex) on the quality of grapes, nectarines, and lettuces (as models of berry fruit, stone fruit, and leafy vegetables) during storage at 2°C (90–95% relative humidity). The active industrial tray showed the best effect on grapes and lettuce quality, as it reduced rachis dehydration and product weight loss (reduced by ≈50% in grapes after 30 days), reduced berry shatter (reduced by ≈40% in grapes after 30 days), highly maintained the physicochemical quality (soluble solid content, titratable acidity and firmness), and also reduced microbial growth (0.5–1.4 lower log units than non-active industrial tray). For nectarines, the package with the biggest active surface (large tray, 200 × 300 × 90) also showed the best-quality retention compared to smaller packages, showing nectarines within active large tray better microbial quality (0.6–1 lower log units than non-active large tray) and firmness. As expected, flow packaging of nectarines (using active trays) better controlled the product weight loss. In conclusion, active cardboard packages with greater active surface better preserved quality of grapes, nectarines and lettuce, which sensory quality was accepted after more than 30, 25, and 14 days at 2°C, respectively, contrary to non-active samples (~1 week less).

PENGARUH VARIASI METERING STROKE TERHADAP CACAT PRODUK CETAKAN INJEKSI PLASTIK

The research aims to analyze the effect of metering stroke on product quality. Metering strokes relate to product weight and mold capacity. The material used is Polyamide (Nylon) 66, using an ENGEL 50ton capacity Injection Molding machine. The research method used is an experimental method before mass pre-production with stroke metering variation as a production parameter. A normality test was used to investigate the experimental data. Shapiro-Wilk's formula on Minitab® software was used to process the data. Product defects caused by an improper metering stroke often in the injection process are short mold and flashing prints. The results show that short mold production defects occur when the metering stroke is 60 mm due to the material does not fill the full cavity. Furthermore, flashing occurs when the metering stroke is 70 mm due to out of cavity capacity. Therefore, the appropriate parameter is a 65 mm metering stroke with good quality part results.

Sistem Pendukung Keputusan Penentuan Jumlah dan Kualitas Sampah Daur Ulang Menggunakan Metode Weight Product

The Sanitation Bureau of Panca Budi Univeristas of Development is a place for the utilization and processing of recycled waste, both organic and non-organic waste. In this case, processed recycled waste will get the best quantity and quality. Determination of the amount and quality of recycled waste using the Weihgt Product (WP) method in order to obtain a quality result of recycled waste that has the best quality as needed. Data collection was carried out by interviewing and conducting research in order to obtain data in the form of exel with a sample size of 22. The data that has been collected, processed and analyzed before being used as input and output as a basis for learning or training. Based on calculations using the product weight method, it can be used as a reference in making a decision support system by weighting, multiplying and dividing each alternative. The value of A11 shows the largest value which is the best alternative choice and based on the test data is cardboard waste. So this research is very appropriate in making the right decision to determine the type of quality waste for recycling.

Recent Development in Micromanufacturing of Metallic Materials

Product miniaturization is a trend for facilitating product usage, enabling product functions to be implemented in microscale geometries, and aimed at reducing product weight, volume, cost and pollution. Driven by ongoing miniaturization in diverse areas including medical devices, precision equipment, communication devices, micro-electromechanical systems (MEMS) and microsystems technology (MST), the demands for micro metallic products have increased tremendously. Such a trend requires development of advanced micromanufacturing technology of metallic materials for producing high-quality micro metallic products that possess excellent dimensional tolerances, required mechanical properties and improved surface quality. Micromanufacturing differs from conventional manufacturing technology in terms of materials, processes, tools, and machines and equipment, due to the miniaturization nature of the whole micromanufacturing system, which challenges the rapid development of micromanufacturing technology. Against such a background, the Special Issue “Micromanufacturing of Metallic Materials” was proposed to present the recent developments of micromanufacturing technologies of metallic materials. The papers collected in the Special Issue include research articles, literature review and technical notes, which have been highlighted in this editorial.