Laichang Zhang
Professor
School of Engineering Edith Cowan University

Speech Title: Mechanical behavior of 3D printed titanium alloy porous scaffolds
Abstract: Beta-type titanium porous structures are a new class of solution for implants because they offer excellent combination of high strength and low Young’s modulus. This presentation studies the influence of porosity variation in 3D printing (via electron beam melting (EBM)-produced and selective laser melting (SLM)) produced beta-type titanium alloy samples on the mechanical properties including super-elastic property, Young’s modulus, compression strength, energy absorption and fatigue properties. Compared with Ti-6Al-4V samples, the beta-type titanium porous samples exhibit a higher normalized fatigue strength owing to super-elastic property, greater plastic zone ahead of the fatigue crack tip and the crack deflection behaviour. Stress distribution results, obtained by finite element methods, coupled with the investigation of the slip bands generated have been used to reveal the plasticity mechanism and local stress concentrations for each structure. The topology optimized structure exhibits the best balance of bending and buckling stress with a high elastic energy absorption, a low Young’s modulus and a high compression strength.

Zhenyu Tian
Professor
Institute of Engineering Thermophysics, Chinese Academy of Sciences

Speech Title:Facile synthesis of transition metal oxides for clean combustion of VOCs
Abstract: In the past few decades, to reduce emissions caused by volatile organic compounds (VOCs), catalytic oxidation has been widely applied and recognized as an efficient and promising technique. This presentation will briefly review a novel and facile strategy to synthesize spinel-type and non-spinel-type transition metal oxides (TMOs). Specifically, single (Co3O4, α-Fe2O3, Mn3O4, CuO, Cu2O and Cr2O3), binary (Co-Mn, Co-Fe, Co-Cu, Fe-Cu, Cu-Mn and La-Co) and ternary (Co-Fe-Cu) TMOs have been prepared using pulsed spray evaporation chemical vapor deposition approach (PSE-CVD). PSE-CVD offers several advantages over conventional methods, such as relatively low cost, simplicity and high throughput, which makes it a promising strategy. The PSE delivery system allows using less stable precursors and permits improving the reproducibility of the film properties with tailored compositions. The above listed TMOs prepared by PSE-CVD were successfully tested as catalysts toward the complete oxidation of some real fuels such as C2H2, C3H6, n-C4H8, C7H8 and C2H6O as representatives of VOCs and industrial exhaust streams. The active TMOs explored in this work could be potential catalysts candidates for future clean energy.

Donatella Giuranno
Full time Researcher
Institute of Condensed Matter Chemistry and Technologies for Energy, National Research Council of Italy

Speech Title: Tailored light-weighting composites by Si-Ti-C system: Experimental and theoretical considerations
Abstract:Light-weight materials capable of bearing load have become increasingly valuable for designing, construction and assembling of lightweight transportation systems such as aircraft, high-speed trains and satellites. To produce competitive advanced MMCs, SiC- and Cf/C-based composites with desirable properties, the reactive infiltration process has advantages over other conventional processing techniques. Currently, three are the greatest open challenges for scientists: theoretical description of the process by computational models, unreacted Si-replacement and “control” of the “pore closure” phenomenon. Key inputs come from the basic know-how on wetting characteristics and reactivity [1], surface properties and thermodynamics.
The interfacial phenomena occurring when liquid Si-Ti alloys are in contact with Glassy Carbon and SiC have been studied. Specifically, five different Si-Ti alloys: both the Si-86at%Ti and Si-16%atTi eutectics, the hypo Si-24at%Ti and hypereutectic Si-8%Ti alloys, as well as the TiSi2 intermetallic compound have been selected.
Wettability, spreading kinetics, reactivity, surface and bulk properties (surface tension and density) as a function of the operating conditions (time, temperature, method) over the temperature range of (Tm+20)÷1500°C have been estimated [2, 3].
The microstructural evolution at the interface have been analyzed by LM, SEM-EDS even at high resolution. In parallel, the results on the surface and bulk properties have been compared with the model predicted values obtained by Ideal solution, Quasi-Chemical Approximation (QCA) for regular solution models [4].
Using basic “know-how” tools, the fabrication and joining of SiC- and Cf/C composites via reactive infiltration of Si-Ti alloys will be presented [5, 6]

Xin Jin
Associate Professor
China University of Petroleum, China

Speech Title:Catalytic conversion of sugars to dicarboxylic acids over bimetallic catalysts
Abstract:Replacing fossil-based feedstocks with renewable resources is considered to be key for reducing carbon emission and environmental pollution. Catalytic conversion of biomass to fuels and chemicals is very important for establishing environment-friendly chemical processes. In this context, aqueous phase oxidation of bio-derived sugars is crucial for sustainable conversion of biomass to value-added carboxylic acids and derivatives. Tartaric acid (TA) has been widely used for additives of food, dyes and pharmaceuticals. However, TA is mainly synthesized via oxidation of Maleic anhydride, a two-step reaction generating significant amounts of toxic substances and waste products. Up to date, there is no detailed study being reported for selective oxidation of sugars to TA using heterogeneous catalysts. Therefore, we proposed AuPt/TiO2 catalyst for facile TA synthesis (50%) from glucose in base-free conditionat 100 °C 10 bar O2.
We systematically studied the transformation of TiO2 crystalline phases to explore the strong Metal-Support Interaction for enhanced oxidation performances. It is found that AuPt nanoparticles supported pure anatase TiO2 and mixed anatase+rutile phases have shown relatively better activity for glucose oxidation compared with pure rutile TiO2(conversion: ). The influence of particle size, as well as metal-metal and metal-support interaction on catalyst performances will be presented in this work. The outcome of this study will provide insights into rational design of effective metal catalysts for oxidation of sugars to value-added chemical

Jie Wei
Postdoctoral
University of Electronic Science and Technology of China

Speech Title:Novel Power Rectifiers and Fabrication Based on GaN Material
Abstract:Wide band gap semiconductor GaN is widely adopted for power devices in recently years. GaN-based power devices allow for greater power efficiency, smaller size, lighter weight, and lower cost, since the GaN material owns high critical electric field, high electron saturation velocity, and high mobility of the 2-dimensional electron gas (2DEG) in AlGaN/GaN to achieve high breakdown voltage (BV), high switching frequency and ultralow on-resistance. GaN-based diodes are promising candidates for microwave and RF applications, while low BV and large leakage current hinder its development. In this speech, three novel high voltage GaN-based diode have been demonstrated. Firstly, an AlGaN/GaN Schottky barrier diode (SBD) with double-heterojunction is theoretically and experimentally investigated on the GaN/AlGaN/GaN/Si-sub. It features two-dimensional hole gas (2DHG) (fixed positive polarization charges) and electron gas (2DEG) (fixed negative polarization charges) at the GaN-top/AlGaN and AlGaN/GaN interface, which allows the proposed SBD to achieve ultralow on-resistance and high BV. Secondly, a novel hybrid-anode diode (HAD) based on ultrathin barrier AlGaN/GaN is theoretically and experimentally investigated. The proposed device, with ohmic contact instead of Schottky anode metal, could modulate the turn-on voltage by delicately designing the threshold voltage of the MIS gate at the hybrid-anode. The novel HAD achieves ultralow turn-on voltage, low on-resistance and low reverse leakage with high BV. Thirdly, a vertical GaN power diode with Fin-shaped anode is proposed. It realizes the rectifying function without Schottky contact, since the electrons in the fin channel are depleted due to the work function difference the anode metal and GaN material. By optimizing device parameters, the proposed Fin-type anode achieves both high BV and low turn-on voltage.