Senior Scientist. Guijun Bi
Singapore Institute of Manufacturing Technology, Singapore
Layer by layer Additive Manufacturing (AM) or 3D Printing of metallic materials has been growing very fast in recent year. With the AM processes complex 3D components can be produced with optimized design. It is a good complementary to the traditional manufacturing processes and shows huge potentials in niche industrial applications in marine, offshore, oil & gas, aerospace, medical devices, automotive petrochemical, etc. The group of metal AM technologies require continuous R&D in materials, software, hardware and processes. In this talk state of the art of the key metal AM technologies will be reviewed. Challenges of metal 3D Printing will be discussed. Advances of the technologies in material development, process simulation, intelligence of the AM systems, machine learning assisted process development and hybrid processes will be highlighted. Future trends of R&D in metal 3D Printing and cases of industry applications will be introduced.
A.Prof. Francis Eng Hock Tay
National University of Singapore, Singapore
Piezoelectric ceramic coatings have shown great application potentials in structural health monitoring and energy harvesting. The thermal spray process has been applied for producing structural and thermal barrier ceramic coatings with the advantages of high productivity, large area coating ability, less limitation of substrates and low cost. However, this has not been established for producing piezoelectric ceramic coatings with complex compositions and perovskite structure that is lead-free.
In this work, barium sodium nitrate (BNT) piezoelectric ceramic coatings with dense morphology and single perovskite phase were fabricated by thermal spray process. The melting and crystallization behaviors of BNT near congruent composition and the effect of excess Bi composition were investigated by analyzing the heating-melting-cooling cycle for the application in thermal spray process. Crystal structure and morphology of the thermal sprayed BNT coatings were examined. The effective piezoelectric coefficient d33 of the heat-treated BNT with both Li and K coating reached 86 pm/V with substrate clamping, measured over macroscale by the laser scanning vibrometer.
Lingnan Normal University, China
Ti(C,N) ceramics have been used widely in cutting tools and molds due to their excellent properties of high strength, high hardness, high temperature oxidation resistance, acid and alkali resistance, and abrasion resistance. However, brittleness has limit its development. Therefore, it becomes extremely urgent and important to speed up the research, development, manufacture, and application of cermet cutting tools in China for the purpose of the development of the global manufacturing powerhouse for China, improving the precision and surface smoothness during high speed machining, increasing the maching efficiency of processing industry, guaranteeing the maching quality, and elevating the level of manufacture industry of cutting tools in China.
In this study YAG-TiCN composite ceramics were prepared by hot pressed sintering with the addition of yttrium aluminium garnet (YAG). The effect of YAG amount on the phase composition, microstructure, and mechanical properties of YAG-TiCN was systematically investigated. The results show that the second phase YAG obviously improved the sintering performance of TiCN, and improved the mechanical properties of the YAG-TiCN composite ceramic. The YAG-TiCN composite ceramic obtained the best mechanical performance when 10% YAG was incorporated. The Vickers hardness, fracture toughness, flexure strength of composite ceramics containing 10% YAG were 20.48 GPa, 7.27 MPa·m1/2, and 570.36 MPa, which were significantly higher than those of pure TiCN ceramics (9.33GPa, 5.5 MPa·m1/2, 204.45 MPa).
Assis.Prof. Yew Ming Chian
Universiti Tunku Abdul Rahman, Malaysia
Development of intumescent fire protective coatings for steel
Intumescent flame-retardant coating (IFRC) offers great prospects for the most efficient utilization of a wide variety of passive fire protection system at the recent development. This article highlights the fire-resistance, physical, chemical, thermal and mechanical properties of the IFRC using Bunsen burner, furnace, Scanning Electron Microscope, freeze-thaw stability test, Thermogravimetri Analysis and Instron Micro Tester. It was found that the incorporation of an appropriate combination of flame-retardant fillers: aluminium hydroxide, calcium silicate, calcium carbonate, expandable graphite and titanium dioxide with flame-retardant additives and polymer binder led to the improvement of fire protection, thermal stability, water resistance and adhesion strength of the coating. Significantly, a novel intumescent fire protective coating with the addition of combinations of flame-retardant fillers have proven to be efficient in preventing fires and maintaining the steel’s integrity by surviving a fire resistance period of 1 hour.