In this work, dolomite filler was introduced into thermoplastic starch (TPS) matrix to form TPS-dolomite (TPS-DOL) biocomposites. TPS-DOL biocomposites were prepared at different dolomite loadings (1 wt%, 2 wt%, 3 wt%, 4 wt% and 5 wt%) and by using two different forms of dolomite (pristine (DOL(P) and sonicated dolomite (DOL(U)) via the solvent casting technique. The effects of dolomite loading and sonication process on the mechanical properties of the TPS-DOL biocomposites were analyzed using tensile and tear tests. The chemistry aspect of the TPS-DOL biocomposites was analyzed using Fourier transform infrared spectroscopy (FTIR) and X-Ray Diffraction (XRD) analysis. According to the mechanical data, biocomposites with a high loading of dolomite (4 and 5 wt%) possess greater tensile and tear properties as compared to the biocomposites with a low loading of dolomite (1 and 2 wt%). Furthermore, it is also proved that the TPS-DOL(U) biocomposites have better mechanical properties when compared to the TPS-DOL(P) biocomposites. Reduction in the dolomite particle size upon the sonication process assisted in its dispersion and distribution throughout the TPS matrix. Thus, this led to the improvement of the tensile and tear properties of the biocomposite. Based on the findings, it is proven that the sonication process is a simple yet beneficial technique in the production of the TPS-dolomite biocomposites with improved tensile and tear properties for use as packaging film.

Aluminium alloy sheets were joined to stainless steel ones by a resistance spot welding method using Al-Mg alloy interlayer. The interlayer exhibits a lower melting point than the Al alloy. Consequently, melted interlayer with a lower temperature filled the gap between the two sheets and resulted in effective joining. Subsequently, tensile shear fatigue tests had been conducted to evaluate fatigue strength and to determine the fatigue fracture mechanism. Resistance spot welding dissimilar welds exhibited higher fatigue strengths than friction stir spot welded dissimilar ones. Fatigue fracture modes were dependent on the load levels, where plug type fracture occurred at high load levels, shear fracture through the nugget at medium load levels and through thickness fatigue crack propagation in the Al sheet at low load levels. The fracture mode transition was attributed to the geometrical rotation around the nugget.

Al alloy sheet was friction stir spot welded (FSSW) to galvanised steel sheet by a scroll grooved tool without probe. Tensile and fatigue tests had been conducted using tensile shear specimens, and the results were discussed in comparison with Al/steel dissimilar FSSW joint, in which steel sheet was not galvanised. Energy dispersive X-ray analyses revealed that Zn coating was melted or softened and circumferentially resolidified around the nugget. Intermetallic compound between Al and Fe was formed along the interface resulting in the joining of Al to steel. Tensile shear strength of Al/galvanised steel weld was lower than that of Al/steel one without galvanising. However, Al/galvanised steel welds exhibited higher fatigue strengths. Finite element method analyses around the nugget revealed that circumferentially resolidified Zn brought about the stress relaxation at the edge of the nugget, resulting in the better fatigue performance of Al/galvanised steel welds.

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Thermoplastic starch (TPS) hybrid bio-composite films containing microcrystalline cellulose (C) and nano-bentonite (B) as hybrid fillers were studied to replace the conventional non-degradable plastic in packaging applications. Raw oil palm empty fruit bunch (OPEFB) was subjected to chemical treatment and acid hydrolysis to obtain C filler. B filler was ultra-sonicated for better dispersion in the TPS films to improve the filler–matrix interactions. The morphology and structure of fillers were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). TPS hybrid bio-composite films were produced by the casting method with different ratios of B and C fillers. The best ratio of B/C was determined through the data of the tensile test. FTIR analysis proved the molecular interactions between the TPS and the hybrid fillers due to the presence of polar groups in their structure. XRD analysis confirmed the intercalation of the TPS chains between the B inter-platelets as a result of well-developed interactions between the TPS and hybrid fillers. SEM images suggested that more plastic deformation occurred in the fractured surface of the TPS hybrid bio-composite film due to the higher degree of stretching after being subjected to tensile loading. Overall, the results indicate that incorporating the hybrid B/C fillers could tremendously improve the mechanical properties of the films. The best ratio of B/C in the TPS was found to be 4:1, in which the tensile strength (8.52MPa), Young’s modulus (42.0 MPa), elongation at break (116.4%) and tensile toughness of the film were increased by 92%, 146%, 156% and 338%, respectively. The significantly improved strength, modulus, flexibility and toughness of the film indicate the benefits of using the hybrid fillers, since these features are useful for the development of sustainable flexible packaging film.

Recently, hybrid fillers have been widely used to improve the properties of biopolymers. The synergistic effects of the hybrid fillers can have a positive impact on biopolymers, including thermoplastic corn starch film (TPCS). In this communication, we highlight the effectiveness of hybrid fillers in inhibiting the aging process of TPCS. The TPCS, thermoplastic corn starch composite films (TPCS-C), and hybrid thermoplastic corn starch composite film (TPCS-HC) were stored for 3 months to study the effect of hybrid filler on the starch retrogradation. TPCS-C and TPCS-HC were prepared by casting method with 5 wt% of fillers: nanocellulose (NC) and bentonite (BT). The alteration of the mechanical properties, aging behavior, and crystalline structure of the films were analyzed through the tensile test, Fourier transform infrared (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and water absorption analysis. The obtained data were correlated to each other to analyze the retrogradation of the TPCS, which is the main factor that contributes to the aging process of the biopolymer. Results signify that incorporating the hybrid filler (NC + BT) in the TPCS/4BT1NC films has effectively prevented retrogradation of the starch molecules after being stored for 3 months. On the contrary, the virgin TPCS film showed the highest degree of retrogradation resulting in a significant decrement in the film’s flexibility. These findings proved the capability of the green hybrid filler in inhibiting the aging of the TPCS.

A person driving a passenger car depends on the rear view mirror and two side-mounted mirrors to observe the surrounding in order to see vehicles approaching from behind. However, the approaching vehicle may enter a region outside the driver's field of view, making it inconspicuous to the driver. Such a region is known as the blind spot zone (BSZ). Although driving schools emphasize the importance of checking for vehicles in BSZ before attempting to change lane, many fatal collisions have occurred during lane changing. Thus, it is important to understand BSZ particularly its corresponding parameters in order to develop an effective system to detect approaching vehicles and provide warning to the driver. In this paper, a systematic approach using a grid-based technique is proposed to model the BSZ. An experiment was conducted using a commonly used passenger car in Malaysia as a test bed to model the BSZ. Controlled experimental parameters were introduced, and the final results showed that BSZ can be identified using the grid-based technique.