An Integrated Experimental–Numerical Approach For Characterizing Deformation Behavior Of High-Strength Steels,
2026
Chulalongkorn University
An Integrated Experimental–Numerical Approach For Characterizing Deformation Behavior Of High-Strength Steels, Weerapong Julsri, Apichat Sanrutsadakorn, Vitoon Uthaisangsuk
Journal of Metals, Materials and Minerals
This study aims to establish an integrated experimental–numerical framework for characterizing the deformation behavior of DP590 high-strength steel sheet. The framework combines experimental uniaxial tensile and Nakajima tests with finite element (FE) simulations to provide a comprehensive assessment of forming limits and fracture behavior. Forming limit curves (FLCs) and forming limit stress curves (FLSCs) were determined with the integrated approach and then validated numerically using the Hill’48 yield criterion together with both Swift and Voce hardening laws. Model calibration incorporated experimental data on directional mechanical properties to ensure that material anisotropy was accurately represented. The FE simulations demonstrated strong agreement …
Controlled Release Of Holy Basil Essential Oil Nanoemulsion Encapsulated In Gelatin/ Carboxymethyl Cellulose Hydrogel For Wound Care,
2026
Chulalongkorn University
Controlled Release Of Holy Basil Essential Oil Nanoemulsion Encapsulated In Gelatin/ Carboxymethyl Cellulose Hydrogel For Wound Care, Shehbaz Ameer, Pranut Potiyaraj, Tu Minh Tran Vo
Journal of Metals, Materials and Minerals
Holy basil essential oil (HBEO) is a therapeutic agent recognized for its antioxidant, anti-inflammatory, and wound-healing properties. However, its clinical use is limited by poor aqueous solubility, volatility, and instability. Nanoemulsion (NE) is an effective strategy to overcome these limitations. In this study, 1% HBEO in 0.5% polyvinyl alcohol (PVA) aqueous solution formulation yielded nanosized droplets (182±3 nm, PDI = 0.286) and showed sustained release, with 92% drug release over 30 h, compared to the rapid release for 1% HBEO in pure water. To further enhance stability and biocompatibility, the HBEO nanoemulsion (HBEONE) was incorporated into a glutaraldehyde (GA) crosslinked …
Novel Eco-Friendly Composites: Crotalaria Pallida (Cp) Fiber Reinforced Guar Gum/ Polyvinyl Alcohol Blends For Enhanced Mechanical And Thermal Properties,
2026
Chulalongkorn University
Novel Eco-Friendly Composites: Crotalaria Pallida (Cp) Fiber Reinforced Guar Gum/ Polyvinyl Alcohol Blends For Enhanced Mechanical And Thermal Properties, Tirupati Rao Bantu, Renjis T. Tom, Delse P. Sebasian, Anitha C. Kumar
Journal of Metals, Materials and Minerals
Eco-friendly composites exhibit promising applications in wound dressings, tissue engineering, sustainable packaging, and environmental cleanup. This study investigates the development of novel biodegradable composites utilizing guar gum (GG), polyvinyl alcohol (PVA), and Crotalaria pallida (CP) fibers, along with wood and nanocellulose, and their characterization. The integration of natural and synthetic polymers with plant fibers enhances mechanical strength, thermal stability, and water resistance. In this study, different loadings of CP material (0.0 g, 0.50 g, 0.75 g, and 1.0 g) and constant amounts of GG and PVA were used to fabricate hybrid films. Fourier Transform Infrared Spectroscopy (FT-IR) analysis revealed significant …
Carbon Precipitation On Metal Nanostructures And Diamond Surfaces,
2026
Chulalongkorn University
Carbon Precipitation On Metal Nanostructures And Diamond Surfaces, Komkrit Rientong, Akkarach Sukserm, Nattakarn Suntornwipat, Udomsilp Pinsook
Journal of Metals, Materials and Minerals
The interaction between diamond and a nickel (Ni) layer plays a crucial role in understanding the formation of graphene and its energy dynamics on metal-diamond substrates. In this study, we investigate the optimal positions of graphene relative to a catalyst layer on diamond by analyzing total energies obtained from self-consistent field (SCF) calculations using Quantum ESPRESSO. The structures of graphene, diamond (100), and the catalyst layers were constructed and simulated both individually and in combination. Energy comparisons between the combined structures and the sum of their individual components were conducted to identify favorable graphene positions. Our simulations show that graphene …
Zinc Oxide Functionalized Biochar From Rambutan Wood As A Novel Material To Utilize An Agricultural Waste In Thailand,
2026
Chulalongkorn University
Zinc Oxide Functionalized Biochar From Rambutan Wood As A Novel Material To Utilize An Agricultural Waste In Thailand, Suchinda Vongsetskul Vongsetskul, Waraporn Thepthong, Supawan Kanyawilas, Narong Chanlek, Ratana Charoenwattanasatien, Wutthikrai Busayaporn, Thammasit Vongsetskul
Journal of Metals, Materials and Minerals
Zinc oxide-functionalized biochar (biochar-ZnO) from rambutan wood, an agricultural waste, was prepared to increase a value of biochar from rambutan, an important economic fruit crop in Thailand, for the first time. Biochar-ZnO was synthesized by a sol-gel process. X-ray diffraction (XRD) spectra suggest that the biochar consists of amorphous carbon mainly and confirm the success of zinc oxide functionalization on the biochar surface. The crystal structure of zinc oxide is hexagonal Wurtzite. The diameter of zinc oxide particles is ~20 nm. Thermogravimetric (TGA) thermograms indicate the success of biochar-ZnO preparation. A weight percentage of zinc oxide in the composite is …
Finite Element Simulation Of Surface Repair Welding Of Grade R260 Railway Rails Using Thermite Welding,
2026
Chulalongkorn University
Finite Element Simulation Of Surface Repair Welding Of Grade R260 Railway Rails Using Thermite Welding, Werayoot Lahamornchaiyakul, Saksit Chuenchomnakjad, Thongchai Khrueaphue, Parinyawatr Dhinnabutra
Journal of Metals, Materials and Minerals
Railway rails subjected to repetitive wheel-rail contact loads experience surface damage, including shallow cracks, groove wear, and material loss. Conventional arc welding repair presents limitations in costs, repair time, and quality consistency. This study investigates thermite welding for surface repair of pearlitic rail steel grade R260, emphasizing the effects of mold overflow configuration on thermal behavior, molten metal flow, and weld quality. A finite element framework incorporating thermal-fluid coupling was developed to simulate temperature distribution and molten metal penetration. Three mold overflow configurations were evaluated: overflow at the wear groove outer edge (Case 1), near the pouring gate (Case 2), …
Castrip Process Technology: Non-Grain Oriented (Ngo) Si Steels Extension And Carbide-Free Bainitic (Cfb) For Flat Products,
2026
Missouri University of Science and Technology
Castrip Process Technology: Non-Grain Oriented (Ngo) Si Steels Extension And Carbide-Free Bainitic (Cfb) For Flat Products, Naram Naidu Meesala
Masters Theses
"This research explores the development of advanced steel grades manufactured through Castrip® twin-roll thin strip casting technology, with particular attention to non-grain-oriented electrical Si-Steels (NGOES) and carbide-free bainitic (CFB) steels. The Castrip® process offers a near-net-shape route for producing thin steel strips, which greatly decreases the number of processing stages, lowers energy demand, and reduces carbon dioxide emissions when compared with traditional steel production methods.
In the NGOES part of the study, several industrial Fe–Si steel compositions were cold rolled to final thicknesses ranging from 0.35 mm to 0.15 mm. These materials were then exposed to short-duration continuous annealing at …
Development Of Stronger, More Extrudable 6xxx Series Alloys For Automotive Applications,
2026
Michigan Technological University
Development Of Stronger, More Extrudable 6xxx Series Alloys For Automotive Applications, Eli A. Harma
Dissertations, Master's Theses and Master's Reports
6xxx alloys are widely used in automotive extrusion structures for their high specific strength and formability. Advanced designs require greater formability and strength, creating an opportunity for high-strength, formable alloys. The 6xxx series forms β”-Mg5Si6 precipitates during age hardening and develops a fibrous microstructure during extrusion, both strengthening the alloy. Increasing Mg and Si to form more β” decreases formability. Thus, modifying texture can increase strength without reducing formability. Current alloys like 6005A add Mn and Cr to form dispersoids that inhibit recrystallization and promote strengthening textures; however, high Mn and Cr concentrations reduce formability. Replacing Mn …
A Review On Biomass-Derived Hard Carbon Anodes For Sodium-Ion Batteries : From Carbon Precursors To Storage Mechanisms,
2026
Chulalongkorn University
A Review On Biomass-Derived Hard Carbon Anodes For Sodium-Ion Batteries : From Carbon Precursors To Storage Mechanisms, Anqi Lu, Jiaqian Qin
Journal of Metals, Materials and Minerals
The rapid development of sustainable energy technologies has intensified the demand for cost-effective and high-performance energy storage systems. Sodium-ion batteries (SIBs) are regarded as one of the most promising alternatives to lithium-ion batteries (LIBs) owing to their low cost, abundant sodium resources, and similar electrochemical mechanisms to LIBs. Hard carbon (HC) has attracted significant attention as the predominant anode material for SIBs due to its low cost, structural tunability, and availability from diverse precursors. Nevertheless, challenges remain, including the unclear Na+ storage mechanism, limited rate capability, and strong dependence on precursor type. This review systematically summarizes recent advances in HC …
Mechanical Properties And Crystallization Of Polybutylene Terephthalate Reinforced With Glass Flakes And Aluminum Powder,
2026
Chulalongkorn University
Mechanical Properties And Crystallization Of Polybutylene Terephthalate Reinforced With Glass Flakes And Aluminum Powder, Nattakarn Hongsriphan, Pajaera Patanathabutr
Journal of Metals, Materials and Minerals
This research investigated mechanical properties and crystallization of poly(butylene terephthalate) composites by adding glass flakes (GF) and aluminum particles (Al). The concentration of the GF was 3 wt% or 5 wt%, and the Al was 0.5 wt% or 1.0 wt%. The stress-strain curves of the PBT-based composites showed yielding and necking. The PBT/GF/Al composites with GF/Al ratios of 3/0.5 wt/wt%, 3/1.0 wt/wt%, 5/0.5 wt/wt%, and 5/1.0 wt/wt% had Young’s moduli of 11.44%, 11.70%, 16.81%, and 19.31% higher than that of neat PBT, respectively. In the presence of Al at 1.0 wt%, the flexural modulus of the PBT/GF/Al composites increased to …
Synthesis, Structure, And Electrochemical Properties Of The Ni(Oh)2/Nimoo4 Composite On The Rgo/Nf Template For Hybrid Battery-Supercapacitor Electrodes,
2026
Chulalongkorn University
Synthesis, Structure, And Electrochemical Properties Of The Ni(Oh)2/Nimoo4 Composite On The Rgo/Nf Template For Hybrid Battery-Supercapacitor Electrodes, Retno Asih, Haniffudin Nurdiansah, Rogabe Sianipar, Ida Ayu Gayatri, Lukman Noerochim, Diah Susanti, Isao Watanabe, Darminto Darminto
Journal of Metals, Materials and Minerals
The growing demand for renewable and sustainable energy has intensified research on advanced energy-storage systems that can deliver both high energy and power densities. In this study, a Ni(OH)2/ NiMoO4 composite on a reduced graphene oxide/nickel foam (rGO/NF) template was synthesized through a hydrothermal and electrodeposition route to construct a hybrid battery-supercapacitor electrode. The unique hierarchical design combines the pseudocapacitive activity of Ni(OH)2/NiMoO4 with the excellent conductivity of rGO and the high surface area of NF, enabling efficient electron and ion transport. Structural and morphological analyses confirm the successful formation of the Ni(OH)2/NiMoO4/rGO/NF architecture. The electrode exhibits a specific capacitance …
Development Of Poly(Lactic Acid)/Ethylene-Propylene-Diene Monomer/Cellulose Composites Using Cellulose Extracted From Hemp Biomass For Plastic Packaging Applications,
2026
Chulalongkorn University
Development Of Poly(Lactic Acid)/Ethylene-Propylene-Diene Monomer/Cellulose Composites Using Cellulose Extracted From Hemp Biomass For Plastic Packaging Applications, Supanicha Alapon, Natthanich Thongmee, Wikoramet Teeka, Pattara Somnuake, Sirirat Wacharawichanant
Journal of Metals, Materials and Minerals
Poly(lactic acid)/ethylene-propylene-diene monomer (EPDM)/cellulose composites using cellulose derived from hemp biomass (CHB) were investigated in this research. Morphology, chemical structures, functional groups, and crystallinity of CHB were characterized, observing a size of 135 ± 32 μm from SEM images with high purity and crystallinity from FT-IR and XRD spectroscopy. The optimized CHB was incorporated at 1 phr, 3 phr, and 5 phr into PLA/EPDM blends at 90/10 w/w. The polymer composites were prepared using an internal mixer, and samples were produced by compression molding for mechanical and thermal testing. The results indicated that the EPDM phase dispersed as droplets in …
Effect Of Cu Content On Microstructure, Morphology, And Antibacterial Properties Of Ti-Cu Alloy Thin Films,
2026
Chulalongkorn University
Effect Of Cu Content On Microstructure, Morphology, And Antibacterial Properties Of Ti-Cu Alloy Thin Films, Chittra Kedkaew, Phalakorn Khwansungnoen, Tanattha Rattana
Journal of Metals, Materials and Minerals
Ti-Cu alloy thin films exhibit considerable potential for the development of advanced antibacterial surfaces, particularly for biomedical applications. In this research, Ti-Cu binary alloy thin films with a wide range of Cu content from 25.8 at% to 77.8 at% were deposited using magnetron co-sputtering with pure Ti and Cu as the targets. The composition of Cu in the films can be controlled by the applied power of Cu targets. This study investigated the effect of Cu content on the microstructural, morphological, and antibacterial properties using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Atomic force microscopy (AFM), X-ray photoelectron …
Contributions Of Carbon Content And Cooling Rate On Phase Transformations And Mechanical Properties Of Sintered Fe-1.5cr-0.2mo-Xc Alloys,
2026
Chulalongkorn University
Contributions Of Carbon Content And Cooling Rate On Phase Transformations And Mechanical Properties Of Sintered Fe-1.5cr-0.2mo-Xc Alloys, Mantana Yaruan, Wantana Koetniyom, Thanyaporn Yotkaew, Nattaya Tosangthum, Ruangdaj Tongsri
Journal of Metals, Materials and Minerals
Microstructural development in sintered Fe-1.5Cr-0.2Mo-xC alloys, produced under different cooling rates of 0.1℃∙s‒1 and 5.4℃∙s‒1, was investigated. It was found that, in slowly sintered Fe-1.5Cr-0.2Mo-xC alloys, the microstructure changed from hypoeutectoid to eutectoid and to hypereutectoid steel microstructural features with increasing carbon content. Under the fast-cooling rate of 5.4℃∙s‒1, the microstructural change with respect to the increase of carbon content involved the competition between the formation of ferrite + carbide mixture and that of martensite-austenite constituent. The increase of tensile strength of slowly cooled sintered Fe-1.5Cr-0.2Mo-xC alloys with increasing carbon content was attributed to …
Effect Of Garnet Incorporation On The Functional Properties Of Sunscreens,
2026
Chulalongkorn University
Effect Of Garnet Incorporation On The Functional Properties Of Sunscreens, Parinya Chakartnarodom, Kanyarat Munmani, Sureerat Polsilapa, Duangrudee Chaysuwan, Wichit Prakaypan, Passakorn Sonprasarn, Edward Laitila, Nuntaporn Kongkajun
Journal of Metals, Materials and Minerals
Garnet, a silicate mineral, was investigated as a replacement for the TiO2-based compound in sunscreen formulations. Samples containing garnet were evaluated for color shade, viscosity, sun protection factor (SPF), and water resistance. Substituting the TiO2-based compound with garnet reduced both viscosity and SPF but markedly enhanced water resistance. This improvement is attributed to the physical reinforcement provided by garnet particles, which strengthen the sunscreen film and reduce wash-off under water exposure. Garnet incorporation also altered the product’s appearance from white to a darker brownish-beige tone, improving visual compatibility with a wider range of skin tones.
Effects Of Welding Currents On Microstructure And Corrosion Behaviors Of Inconel 625 Cladding On 2.25cr-1mo Steel By Hot-Wire Tig,
2026
Chulalongkorn University
Effects Of Welding Currents On Microstructure And Corrosion Behaviors Of Inconel 625 Cladding On 2.25cr-1mo Steel By Hot-Wire Tig, Supparat Saeheng, Hein Zaw Oo, Prapas Muangjunburee
Journal of Metals, Materials and Minerals
Hot-wire tungsten inert gas (HW-TIG) cladding has been applied to the steam turbine rotor welding repair. This study investigated the effects of welding currents on microstructure, hardness, and corrosion behavior. The experiments were conducted using four different welding currents applied to bead-on-plate Inconel 625 welds on a 2.25Cr-1Mo steel substrate as the steam turbine rotor material. The selected welding currents were 125 A, 150 A, 175 A, and 200 A. The percentages of weld dilution for different welding currents were also evaluated. Higher welding currents increased weld dilution, weld bead width, and HAZ size. As the welding current increased, the …
Properties And Printability Of Polylactic Acid Films : An Effect Of Polyglutamate Coated Natto As A Bio-Plasticizer,
2026
Chulalongkorn University
Properties And Printability Of Polylactic Acid Films : An Effect Of Polyglutamate Coated Natto As A Bio-Plasticizer, Natrata Thitinardwong, Thira Chavarnakul, Kawee Srikulkit
Journal of Metals, Materials and Minerals
Polylactic acid (PLA) film, a biodegradable alternative to petroleum-based plastics, has gained significant attention for sustainable packaging applications. However, its limited screen-printability remains a barrier to broader commercial use. This study aims to enhance the screen-printability of PLA film by incorporating a polyglutamate coated natto (designated as Nat-M). PLA/Nat-M films having 1%, 3%, and 5% Nat-M were prepared and evaluated for their key performance indicators, including ink adhesion (ASTM D3359), tone reproduction accuracy, and printing resolution. The screen-printing resolution was optimized between 400 DPI and 500 DPI (dots per inch) to achieve optimal tone reproduction and edge sharpness. Additionally, ink …
A Top-Electrode-Based Liquid-Solid Triboelectric Nanogenerator For Energy Harvesting And Ethanol Detection,
2026
Chulalongkorn University
A Top-Electrode-Based Liquid-Solid Triboelectric Nanogenerator For Energy Harvesting And Ethanol Detection, Subrat Bhol, Nakul Charan Sahu, Sunit Gaurav Mohanty, Vicky Raj Maddala, Basanta Kumar Panigrahi, Premkumar Bhosale
Journal of Metals, Materials and Minerals
Liquid-solid triboelectric nanogenerators (LS-TENGs) offer a promising avenue for self-powered energy harvesting and sensing by exploiting contact electrification at fluid-dielectric interfaces, where droplet dynamics drive charge separation for electrical output without external power. In this work, a top-electrode LS-TENG was fabricated using a polytetrafluoroethylene (PTFE) film on a PMMA substrate with deionised water droplets, achieving an open-circuit voltage of ‒3.4 V, short-circuit current of 3.6 μA, and peak power of 1.48 nW at 100 MΩ under optimised conditions of 2 cm drop height, 45° tilt, and 50 μL volume. Performance scaled with droplet kinetics and volume due to enhanced contact …
Strategic Optimization Of Plasticizers, Fillers, And Blend Ratios For Enhanced Performance Of Dynamically Cured Epoxidized Natural Rubber (Enr)/Polypropylene (Pp) Thermoplastic Vulcanizates,
2026
Chulalongkorn University
Strategic Optimization Of Plasticizers, Fillers, And Blend Ratios For Enhanced Performance Of Dynamically Cured Epoxidized Natural Rubber (Enr)/Polypropylene (Pp) Thermoplastic Vulcanizates, Azizon Kaesaman, Anuwat Worlee, Charoen Nakason
Journal of Metals, Materials and Minerals
This study introduces an innovative methodology for optimizing oil, plasticizer, filler, and blend proportions in epoxidized natural rubber with 20 mol% epoxide (ENR-20) and polypropylene (PP) thermoplastic vulcanizates (TPVs), aiming to achieve superior rheological, mechanical, morphological, and thermal performance. By leveraging paraffinic oil, epoxidized soybean oil, and phthalate-based plasticizers, the research investigates their influence on tensile strength, elasticity, and processability. Among the oils and plasticizers evaluated, paraffinic oil demonstrated the most effective plasticizing performance, offering superior flexibility and elasticity. Various paraffinic oil loadings (15 phr, 25 phr, 30 phr, 35 phr, 40 phr, 45 phr, 50 phr, and 75 phr) …
Impact Of Chromium Substitution On Structural And Magnetic Properties Of Mnbi-Based Melt-Spun Ribbons,
2026
Chulalongkorn University
Impact Of Chromium Substitution On Structural And Magnetic Properties Of Mnbi-Based Melt-Spun Ribbons, Anh Kha Vuong, Triet Minh Dang, Truong Xuan Nguyen, Duy Anh Vo Nguyen, Hai Van Pham, Nam Hoai Nguyen, Nam Hong Pham, Oanh Kim Thi Vuong, Tan Nhut Nguyen Le, Tuan Van Dinh, Nam Thanh Tran Nguyen, Nhan Thi Tran, Trung Quoc Nguyen, Nhan Thi Tran, Trung Quoc Nguyen, Lu Wei, Vuong Van Nguyen
Journal of Metals, Materials and Minerals
MnBi-based magnetic materials and magnets are of significant interest due to their magnetism without rare earth elements and their ability to replace Nd-Fe-B in high-temperature magnet applications due to its unique feature of enhancing coercivity in the range of 100℃ to 250℃, enabling their energy product (BH)max comparable to NdFeB magnets despite their moderate spontaneous magnetization Msp. To adjust the magnetic properties of MnBi magnets, various elements have been doped to regulate magnetic interactions among the atoms, which subsequently alters Msp and the magneto-crystalline anisotropy energy. In this work, we investigate the effects of chromium doping on the magnetic properties …
