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NUMERICAL EVALUATION OF HOT STAMPED BLANK B-PILLARS
No full textThe recent advances in sheet metal forming simulation technology have allowed engineers to predict the sheet metal stamped part performance prior to mass pro-duction by finite element method. However, the accuracy of such simulation meth-od is dependent on many factors such as right material model and its boundary con-ditions. This thesis describes the application of this method in the evaluation of an automotive hot stamped structural part call B-pillar and its variants. The first case study involved the optimization of spot-weld points and locations on a Patchwork blank B-pillar (PWB) made up of two blank materials of different thicknesses. The spot weld was modeled as a rigid link between the parent blank and the additional blank. Throughout the forming simulation, maximum stress and formability of the part were monitored. The same procedure was repeated by increasing the number of spot-weld points and locations. An optimum number of the spot-weld was then de-termined by the onset of wrinkle disappearance. Performance of the optimized spot-weld part was validated by the actual part. The results show the optimum number of spot weld points as predicted by the simulation is between 35-40 whereas the actual part contains 40 spot-weld points. The second case study was to evaluate the crash worthiness performance of different designs of hot formed B-pillars. In this study, in addition to PWB, three other hot formed B-Pillar designs namely Monolithic blank (MB), Tailor welded blank (TWB) and Tailor Rolled Blank (TRW) were evaluated by numerical simulation in accordance with the Insurance Institute for Highway Safety (IIHS) side impact test protocol.. For each design, maximum displacement or intrusion and energy absorption were measured. The results of intrusion tests for all blank models MB, PWB, TWB and TRB recorded displacement of 14.14cm, 14.80cm, 14.87cm and 14.98cm, respectively. These are considered as within the SAFE ZONE as specified by IHSS. However, in terms of energy absorption, the PWB is seemed to be the best performer followed by MB, TRB and TWB. More importantly, the FEM model developed in this research is quite reliable in determining the optimum number of spot weld points
Effect of Kenaf Fibre Size on Mechanical, Thermal and Physical Properties of Hybrid Kenaf/Wollastonite Reinforced PP Composite
No full textThis article is index by ScopusA previous study demonstrated that incorporating kenaf, a natural fibre celebrated for its sustainability, at 15 wt% and wollastonite, a mineral filler, at 5 wt% into a polypropylene (PP) matrix resulted in the highest tensile properties among various hybrid composite formulations. This study explores the influence of kenaf fibre size (< 300 µm, 300–599 µm, and 600–849 µm) on the performance of these hybrid composites. Mechanical tests (tensile, flexural, and impact resistance), thermal analyses (DSC and TGA), and physical evaluations (density and water absorption) were performed. The results reveal that fibre size has a significant impact on composite performance. Smaller fibres improved tensile properties and flexural strength due to better dispersion and stronger fibre-matrix interactions. Medium-sized fibres demonstrated the highest impact strength (3.206 kJ/m2), whereas composites with larger fibres exhibited increased moisture absorption (2.5%). Physical properties, such as density, remained consistent across all samples (0.953–0.955 g/cm3). Thermal stability analyses through TGA and DSC showed minimal variation among fibre sizes, indicating comparable resistance to thermal degradation. These findings suggest that optimizing fibre size, particularly using smaller kenaf fibres, can enhance mechanical performance and water resistance without compromising thermal stability. The study highlights the potential of kenaf/wollastonite-PP composites in sustainable applications, particularly in the automotive and construction industries, offering valuable insights for the design and optimization of bio-based materials
Optimization of adsorption parameters of bromocresol green dye and Acacia mangium wood activated carbon: Kinetics, thermodynamics, isotherm, and surface interaction mechanism
No full textThis article is index by ScopusThis study aimed to optimize the adsorption capacity of Acacia mangium wood activated carbon (AMW-AC) against bromocresol green (BCG) dye using a face-centered central composite design of response surface methodology (RSM). The variables considered for optimization are AMW-AC dosage (0.5-1.5 g/L), contact time (30-120 min), and BCG dye initial concentration (50-300 mg/L) to maximize the adsorption capacity (mg/g) of AMW-AC. The statistical design resulted in a quadratic model with only two significant factors: adsorbent dosage and initial concentration of BCG dye. The contact time was not an important factor because the adsorption was quick, and maximum adsorption occurred within 30 minutes of the contact time. The adsorption capacity data fit well in the proposed RSM model, which indicates that the control change in independent variables (AMW-AC dose, contact time, and initial BCG dye concentration) regulated the variability in the response (adsorption capacity). The optimal value of independent variables for the maximum adsorption capacity of AMW-AC (580.4 ± 11.4 mg/g) was 0.5 g/L of AMW-AC dosage, 30 min of contact time, and 300 mg/L of BCG dye concentration. The kinetic data of BCG dye adsorption followed the pseudo-second order model, and the isotherm data fit well with the Freundlich isotherm model (predicted qmax 586.22 mg/g). Thermodynamic evaluation of BCG dye adsorption data revealed that adsorption was exothermic and spontaneous. This study also illustrated the BCG adsorption mechanism. The AMW-AC adsorbent surface is mostly comprised of C, N, O, and P-based functional groups