INTL. SYMP. ON ADVANCED MANUFACTURING FOR SUSTAINABLE DEVELOPMENT

Because the strength, toughness and other engineering properties of heterogeneous materials are strong dependent on their grain size and density, the quest to achieve simultaneously dense and fine, ultrafine and nanostructured grain size materials has been one of the most important in materials science and engineering. In this work we explore novel approaches for producing dense and fine, ultrafine and nanostructured heterogeneous materials. Typical approaches consist of acoustic cavitation, high energy planetary ball milling, reaction synthesis, and shock synthesis and modified spark plasma synthesis, followed by dynamic and static consolidation and densification pre and post reaction synthesis. Typical heterogeneous multiphase, multi microstructural constituent materials covered in this work consist of tungsten heavy alloys, coated graphite powders, metal silicide and aluminides and ceramic composites. The synthesized and densified materials were fully characterized by OM, SEM, TEM, EDX analysis, quantitative image analysis, X-Ray diffraction and mechanical testing. This paper presents and discusses the effect of reaction and processing parameters on the microstructure, densification, strength and toughness of typical heterogeneous materials and their application into the manufacture of advanced components and devices.

Crystallite size is a primary determinant of the mechanical properties in solidified alloy deposits, and thus it is in need of predictive modeling. This project reports on employing uniform droplet spraying (UDS) [1] as a paradigm for solidification modeling of mono-size solid droplets in an oil bath, as well as planar and globular splats on a cooling substrate for AZ₉₁D and Mg₉₇ZnY₂ alloys [2]. The model combines a nucleation and dendrite fragmentation description from solidification theory with a framework for constrained growth of crystalline domains confined by adjacent developing ones [3]. The latter is based on differential attributes of the dynamic temperature field during solidification, derived from semi-analytical expressions for the simple droplet and splat geometries above. The model parameters are calibrated and its predictions are validated against measured domain size distributions on section micrographs, and found to be within a -10% to +14% estimation error range. Further improvement of the model via numerical thermal descriptions for off-line material design and optimization in additive manufacturing is discussed [4], along with its use as a real-time structural observer for closed-loop control based on temperature measurements in UDS-based processes.

Recent progress in sensor and biosensor research and technology has lead to their integration in products designed for healthcare monitoring. This is due to their important properties such as reduced sizes, cost effective, lightweight, and high sensitivity. Recent estimates, however, show that the biosensor and electrochemical sensor market are dominated by glucose sensors. Therefore, there is a great need to expand the application of sensors and biosensors beyond glucose. Furthermore, taking into account the rapid development of society’s needs, concepts such as intelligent clothing and wearable devices receive increasing attention. In addition, new features such as portable, flexible, and real-time monitoring are becoming more and more important.
In the last years, recent approaches are focused on wearable electrochemical sensors which can detect target analytes in saliva, tears, sweat, and interstitial fluid.
The aim of this work is the development of an original flexible and wearable biosensor based on nanocomposite materials (polymers and graphene) fabricated by laser-induced forward transfer (LIFT). In particular, we focus on the synthesis of donor materials and the optimization of the LIFT process for obtaining reproducible pixels which are used as electrodes for the electrochemical biosensors. We printed different polymer:graphene nanocomposites onto flexible substrates (coated with an insulating layer, for ex. Parylene C, which prevents electrical contact with the body fluids). The biosensors fabricated by LIFT are used for the detection of heavy metals in human body fluids. Promising results, i.e. high sensitivity and detection limits, were obtained. This proves that LIFT may be used as an alternative method for printing nanoscale materials aimed at the fabrication of wearable sensors.

For many years, the detection of explosives and illegal drugs has been a major challenge which aligns with the speeding process of globalization. In particular, the illicit drug market is in continuous growth, as indicated by the 2.4 million drug seizures made by law enforcement. Therefore, the demand for alarm technologies that can be effectively used for developing illicit drug and explosives detection sensors becomes even more urgent.
Under this point of view, electronic nose (e-nose) technologies meet all the above requirements, combining the data obtained by a sensor array selected for target application with computational intelligence to make an efficient chemical detection system. Of the various e-noses developed, the ones based on surface acoustic wave (SAW) devices are among the most sensitive. In addition, SAW vapor sensors are fast, highly sensitive and reversible. Their fabrication methods are compatible with standard integrated circuit technology, which makes them suitable for volume production and, hence, for cost reduction.
Nowadays, however, e-noses based on SAW vapor sensors are used only for some very specific applications like detection of explosives and warfare agents. One of the main reasons for lack of a commercial development of SAW e-noses could be related to the available deposition techniques for the sensitive layers. In fact, SAW sensors require a uniform (i.e. continuous, uniform in thickness and hole-free) active layer along the wave propagation path in order to prevent high attenuation and degradation of the Q-factor. In this work, we will show that we can use different nanocomposites, i.e. polymers (for example poly[3-(6-carboxyhexyl)thiophe-2,5-diyl]) : graphene, as active materials. These could be printed solvent free by the laser (no clogging of nozzles or creating of special inks) and show sensitivities below 100 Hz/ppm for dimethyl methylphosphonate (a simulant for sarin gas), dichloromethane and ethyl acetate.
The SAW e-nose system is based on an array configuration composed of six SAW resonators coated with five different polymers, plus an uncoated SAW device used as reference. In particular, laser-induced forward transfer was applied for the coating of SAW sensors with different nanocomposite layers. The nanocomposites as active materials detect different chemical interaction affinities of the vapors in a manner in which pattern recognition methods succeed in discrimination between target vapor classes and interferents.

The results of the study of structures and mechanical properties of ceramic materials will be discussed. These ceramic materials were obtained by hot pressing from the submicron AlB₁₂C₂ and AlB₁₂ powder [1], with and without the addition of TiC, as well as from B₄C, without and with SiC additions. Temperature, pressure and composition of the starting powder are optimized to obtain sintered bodies with desired high mechanical characteristics. X-ray diffraction, scanning electron microscopy and Raman microspectroscopy are utilized to investigate phase composition and microstructure of the sintered ceramics. High compression strength (1551 MPa for B₄C, 1878 MPa for B₄C-SiC-based material and 795 MPa for AlB₁₂C₂-TiB₂ based material) together with high bending strength, hardness, fracture toughness, and a light weight make the synthesized and sintered ceramics very promising as a shock-wave resistant material. The effect of C, TiC and SiC additions on the properties of the resultant composites and the particularities of the ceramics destruction under shock loading will be discussed. The results of the modeling of ballistic characteristics will be discussed. The performed ballistic tests of 10 mm thick plates from the developed ceramic had a 2.63 g/cm³ density as well as a composition of 78 wt.% of B₄C and 22 wt.% of SiC according to X-ray diffraction analysis. According to SEM microprobe X-ray analysis, stoichiometries B_3.64CSi_0.01 and SiC_1.07, respectively, showed that the plates can withstand the shot of a B32 bullet with kinetic energy of 3.7 kJ from a 10 m distance.

The polish way of nuclear fusion will be described. The author will present some historical experiments performed by S.Kaliski’s team and some new alternative methods for nuclear fission, including his proposals of plasma stabilisation methods in plasma-focus arrangements. The high speed gas jet and some effects of laser-plasma interaction are used. Contrary to experiments led in Warsow by S.Kaliski, low-cost experiments led by the author had only one distinctive character and were realized at low energy densities. Obtained results, however, suggest the desirability of further research which would be performed in conditions that approach high-energetic systems of plasma-focus or laser-plasma-focus. With the sentence of the author, new mathematical tools will perform the essential role of designing new experiments. Their closer characteristics will become contained in the monograph prepared for the publication in the next year. The obtainment of the fusion reaction is not a critical problem for thermonuclear energetics today. The fusion reaction was obtained on the laboratory-scale, using both the inertial method (in Warsow, Sylwester Kaliski team) and in low-pressure-arrangements of Tokamak (in Nagoya Noria Aray team). The lifetime of the reactor and its economic profitability is a current problem. Inertial reactors, especially reactors of the plasma-focus type, are more permanent and significantly cheaper from reactors of the TOKAMAK type. Several ideas, probably leading to further increase of the durability of the inertial reactor elements, will be presented in the paper. Unfortunately, the several problems waiting for solutions must also be presented.
In spite of the success of the experiments realized in Warsaw in the years 1974-78, works on the construction of the reactor able to have practical meaning were not undertaken. The most persons from prof. Kaliski’s team are not alive. The proposed presentation is dedicated to their memory.

Manufacturing remains the largest and most important wealth generating sector. Within this sector, material removal is a key technology in the aerospace and automotive industries, contributing to more than $200 billion of the economy in North America on an annual basis. The demand for high productivity and high accuracy is steadily increasing, along with the increasing attention to the impact on the environment. In this work, only conventional machining processes are discussed.
A system approach to the machining system is presented in terms of its elements (machine, tool, workpiece and fixture), properties (materials, configuration, contact interfaces) and interactions (dynamic, tribological, thermal, thermo-elastic) to set the framework for predicting the system response (quality attributes and machining-induced defects) to the operational input. This input describes controlled cutting conditions and uncontrolled dynamic-tribo-thermo-elastic self-induced changes. The impacts of this new approach on the environment will be explored.
The paper provides a critical assessment of the current status of removal technologies of sustainable material. The paper also assesses the research effort towards the development of new and hybrid sustainable machining strategies and processes for: (a) high speed/high performance machining and tool life management, (b) machining of composites and stacked materials, (c) high performance/superabrasive advanced grinding and polishing, and (d) physics-based modeling and simulation of the machining system to achieve a virtual machining environment for the realization of sustainable development philosophy. Life cycle analyses of these technologies, which proved to be effective for applications that involve aggressive metal removal, especially for hard-to-cut materials, are discussed and compared to flood machining. They are compared in terms of their environmental impact on human health, ecosystem quality and natural resources (materials and energy). The effect of MQL and cryogenic machining on the surface integrity of machined surfaces and the reduction in cutting forces, surface roughness and tool wear are presented.