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In the previous study, hybrid crash box combines low-density and high-strength of composite materials with aluminium materials had been developed. In this study, circular hybrid crash box with friction model is investigated. Crash box design is modelled by using computer simulation with ANSYS Workbench. Composite Carbon Toray T300 – Epoxy Resin (CCE) and metal Aluminium Alloy 6063 (AA6063) is used as hybrid crash box material. Axial loading with a speed of 10 m/s is applied to circular hybrid crash box model by using impactor with mass of 100 kg. The orientation angle of composite lay-up and hybrid material configuration with two models of friction was running as 16 models. Energy absorption and deformation pattern were observed to determine crashworthiness performance. Based on the results, it can be denoted that the Al-Ko45 with friction model of 0,68 shows largest energy absorption of 7,53 kJ with specific energy absorption of 32,552 kJ/kg. The deformation pattern produces mixed mode with progressive crushing folding that can enhance energy absorption

In the previous study, Continuous Drive Friction Welding (CDFW) had been investigated to determine the strength of joining, burn off, and temperature distribution. In this study, Dissimilar Metal CDFW was studied to assess temperature cycle analysis. Aluminum 6061 (A6061) workpiece was fixed, and an AISI 304 was rotated at 1,000 rpm. The temperature distribution was measured by using an OMEGA Thermocouple Data Logger. The thermocouple was installed near joining location 5 mm distance from the joint. In the computer simulation, the geometry of CDFW was designed using ANSYS Design Modeler. Computer simulation with transient thermal combined with static structural analysis was modeled by using ANSYS academic version Rel. 18.1. The boundary condition was set based on the experimental condition, where the Aluminum 6061 was fixed, and the AISI 304 was rotated at 1,000 rpm. Based on the experimental results, the temperature profile as the outer surface of the distance of the center of the joint location can be measured. From the simulation results, it can be seen that the temperature cycle profile is the same trend with experimental results. The mechanical properties provided that this phenomenon is shown in the characteristics of tensile strength, microstructure and hardness test as model analysis to denote the connection from temperature cycle profile with mechanical properties test results. Microstructure observation revealed that there is no significant difference in grain size and grain shape on the stainless steel side. Computer simulation results showed that the welded aluminum-stainless steel joint shows marks of heat affected zone near the weld interface only on the aluminum side, and this was confirmed by experimental results

Battery waste is one of waste that can damage the environment and there has not been much good processing in Indonesia. Even though, battery waste contains carbon which can be used as a target material for deposition of carbon films using plasma sputtering. The focus of this research is to determine the effect and optimum power value of plasma argon generation, so that the power generation value can produce the highest hardness value of SKD11 steel can be obtained. The method used as plasma is argon gas. Argon plasma is generated by using a 40 kHz LGF. Thin film of carbon synthesize on SKD11 steel was tested to determine the value of hardness using micro hardness Vickers. Based on the experimental result, the optimum power treatment obtained at 340 Watt with the highest average hardness value is 316.7 HV. Based on SEM-EDX observation, it can be described that comparison of atomic carbon from carbon rods without treatment (1.5 %) and carbon thin films on SKD11 with optimum power treatment (13.36 %) show different value. Number of atomic carbon of thin films on SKD11 with power treatment more higher than atomic carbon of carbon rods without treatment, it causes higher hardness value of thin films on SKD11 steel after plasma sputtering treatment on optimum power parameters than SKD11 steel without treatment. SKD11 steel that has a high hardness value used as dies, forming, and cutting that requires high hardness performance, Аккумуляторные отходы – это отходы, которые могут нанести вред окружающей среде, и в Индонезии до сих пор не налажена их качественная переработка. Хотя отходы батарей содержат углерод, который может быть использован в качестве целевого материала для осаждения углеродных пленок с использованием плазменного распыления. Целью данного исследования является определение эффекта и оптимального значения мощности генерации плазменного аргона для получения максимальное значение твердости стали SKD11, обеспечивающее выработку мощности. В данном методе используется плазма в виде аргона. Аргоновая плазма генерируется с использованием LGF 40 кГц. Тонкая пленка углерода, синтезируемая на стали SKD11, была испытана для определения величины твердости с использованием микротвердости по Виккерсу. Исходя из результатов эксперимента, оптимальная мощность, полученная при 340 Вт с самым высоким средним значением твердости, составляет 316,7 HV. Основываясь на наблюдении SEM-EDX, можно описать, что сравнение атомарного углерода из углеродных стержней без обработки (1,5 %) и углеродных тонких пленок на SKD11 с оптимальной энергетической обработкой (13,36 %) показывает разные значения. Количество атомарного углерода тонких пленок на SKD11 с энергетической обработкой выше, чем у атомарного углерода углеродных стержней без обработки, обусловливает более высокое значение твердости тонких пленок на стали SKD11 после обработки плазменным напылением по оптимальным энергетическим параметрам, чем у стали SKD11 без обработки. Сталь SKD11, имеющая высокое значение твердости, используемая в качестве штампов и резки, требует высоких показателей твердости, Акумуляторні відходи - це відходи, які можуть завдати шкоди навколишньому середовищу, і в Індонезії досі не налагоджена їх якісна переробка. Хоча відходи батарей містять вуглець, який може бути використаний в якості цільового матеріалу для осадження вуглецевих плівок з використанням плазмового розпилення. Метою даного дослідження є визначення ефекту і оптимального значення потужності генерації плазмового аргону для отримання максимального значення твердості стали SKD11, що забезпечує вироблення потужності. В даному методі використовується плазма у вигляді аргону. Аргонова плазма генерується з використанням LGF 40 кГц. Тонка плівка вуглецю, що синтезується на сталі SKD11, була випробувана для визначення величини твердості з використанням мікротвердості по Віккерсу. Виходячи з результатів експерименту, оптимальна потужність, отримана при 340 Вт з найвищим середнім значенням твердості, становить 316,7 HV. Ґрунтуючись на спостереженні SEM-EDX, можна описати, що порівняння атомарного вуглецю з вуглецевих стрижнів без обробки (1,5%) і вуглецевих тонких плівок на SKD11 з оптимальною енергетичної обробкою (13,36%) показує різні значення. Кількість атомарного вуглецю тонких плівок на SKD11 з енергетичної обробкою вище, ніж у атомарного вуглецю вуглецевих стрижнів без обробки, обумовлює більш високе значення твердості тонких плівок на сталі SKD11 після обробки плазмовим напиленням за оптимальними енергетичними параметрами, ніж у сталі SKD11 без обробки. Сталь SKD11, що має високе значення твердості, що використовується в якості штампів і різання, вимагає високих показників твердості

This study aims to find out the influence of the university's role on the implementation of eco-innovation in the creative industry in the natural stone handicraft sector. The object of this research is the creative industry center of the marble and natural stone handicraft sub-sector in TulungagungCity, Indonesia. From the existing craftsmen population, 81 craftsmen as respondents were taken as samples. The research data was obtained by distributing questionnaires, then the data were tested, processed and analyzed using Partial Least Square Consistent - Structural Equation Modeling (PLS-SEM). The results of this study states that the role of the university in the implementation of eco-innovation in the industry center of natural stone handicraft in Tulungagung can significantly improve eco-organizational innovation, eco-process innovation and eco-marketing innovation, but not significant in improving eco-product innovation. To further improve the implementation of eco-product innovation, what needs to be improved is the role of the university in assisting to increase eco-marketing, because of its significant influence on eco-product innovation. The results of this study will later be developed to explain the concept of triple helix, namely the role of University, Industry and Government in the implementation of eco-innovation and the improvement of the performance of creative industrial centers of natural stone crafts in Tulungagung Indonesia.

Friction welding is a solid-state joining technique. It is suitable to be used to join a round bar of aluminum that has problems in joining. This paper reports measurements of the tensile strength and fatigue crack growth rate of a continuous drive friction welding (CDFW) joint of aluminum alloys A6061. The CDFW process was conducted by using the round bar A6061 machined to form a chamfer angle and applying a clamping process before the upset stage. Various chamfer angles of 0, 30, 45, and 60 degrees were machined on the stationary round bar. In order to increase the tensile strength and to reduce the fatigue crack growth rate of the CDFW joint, round clamps were applied on the CDFW joint. CDFW process was conducted with the revolution speed of 1,100 rpm, the initial compression force of 3.9 kN during friction stage for 4 seconds, and an upset force of 28 kN for 60 seconds. The specimens of friction weld joints were machined to shape the specimens of tensile strength testing and fatigue crack growth testing. Fatigue crack growth testing was performed using a cantilever rotary bending machine. The testing results show that using a small chamfer angle together with the round clamp produced a CDFW joint that exhibited higher tensile strength than the joint without chamfer or clamping. The specimen created with a chamfer angle of 30 degrees and the clamping method had the highest tensile strength and the lowest fatigue crack growth rate among the samples studied. This result was caused by smaller heat input as a result of using a small one-sided chamfer together with two stages of plastic deformation from the clamping process and upset process during CDFW. The fatigue crack growth rate is also confirmed by macro and scanning electron microscope imaging of the fracture surfaces. The area of fatigue crack growth of the specimen with high tensile strength is wider than the specimen with lower tensile strength. The striations are also observed more clearly in the fracture s

The fluid of vegetable Aloe Vera has characteristics as a cutting fluid, Aloe Vera cutting fluid (AVCF) has an excess of environmental reduction effects from oil-based cutting fluid (OBCF). Surface Response Methodology (RSM) based Central Composite Design (CCD) was applied as an experimental design, to predict the optimum parameters in the turning process. Because RSM is the final description of a good experimental design to improve the linear response surface model, and in determining the optimum operating conditions. Twenty sets of experimental tests were prepared by three reversed parameter factors, feed rate (f), depth of cut (a), and AVCF three type. Roughness (Ra) and flank wear (VB) were defined as response variables and then analyzed by multiple quadratic regression to determine the most appropriate mathematical model. The combined effects of the parameters were investigated using contour plots and surface plots. HSS as a cutting tool and Steel St.42 workpiece were used to achieve 20 tests. The adequacy of the developed model was examined using Analysis of Variance. Based on the results, the optimum process is shown by the following parameters: f=0.140 mm/rev; a=2.0556 mm, and AVCF=71.8970 cSt provide optimal cutting conditions with lower Ra and f=0.20 mm/rev, a=2.50 mm, and AVCF=8.8050 cSt giveoptimal cutting conditions with lower VB. Therefore, the improvement of AVCF as a substitute for OBCF continued experiments.

In the current study, the effect of friction coefficient on strain distribution and deformation was investigated with the computer simulation providing a better understanding of the material flow mechanism and deformation behavior in the ECAP. The 10×10 mm and 50 mm-long rectangular billet was used as the geometry of aluminum material. The geometry of dies is 105° channel angle, 0 mm inner fillet radius, and 5 mm outer fillet radius. The dies were modeled as rigid bodies, and the specimen was assumed as a bilinear hardening model. The effect of friction was investigated with the three-level variation coefficient of friction (0.01; 0.025 and 0.05). Based on the result, it can be shown that the friction affects the strain distribution condition. The friction of 0.05 produced more uniform strain distribution, better homogeneity, and smaller corner gap. The experimental study of modeling results was done with MoS2 lubricant while the strain distribution was verified by the microhardness test. The microhardness distribution test result was similar to strain distribution from modeling., На основі комп'ютерного 3D-моделювання виконано дослідження впливу коефіцієнта тертя на деформацію та її розподіл для зразків з алюмінієвого сплаву 5052. Ефект тертя був досліджений за трьома рівнями варіації коефіцієнтів тертя (0:01; 0025; 0:05). Результати дозволили зробити висновки щодо характеру розподілу та чисельних значень деформації та мікротвердості для різних коефіцієнтів тертя, На основе компьютерного 3D-моделирования исследовано влияние коэффициента трения на деформацию и ее распределение для образцов из алюминиевого сплава 5052. Эффект трения был исследован для трёх уровней вариации коэффициентов трения (0:01; 0025; 0:05). Результаты позволили сделать выводы о характере распределения и численных значениях деформации и микротвердости для различных коэффициентов трения