Bangwei Zhang

Recent progress in nanoethics and its possible effects on engineering education

Nanotechnology can improve many physical, chemical, physicochemical, and biological properties of materials, which can be very useful for many industries, including the biomedical, aerospace, textile, cosmetics, manufacturing, oil, agricultural, defense, and electronics industries. However, nanotechnology products (or nanomaterials) can be hazardous because of the way they are manipulated on an atomic scale. Since nanomaterials, such as nanotubes, nanoparticles, nanowires, nanofibers, nanocomposites, and nanofilms, are all new, produced with entirely new manufacturing techniques, there are no specific rules and regulations for them. In the present nanoethics study, we provide a detailed report of the ethical, social, philosophical, environmental, safety, and legal issues surrounding nanotechnology and its products, which can be very useful for the training and protection of students, as well as scientists, engineers, policymakers, and regulators working in the field.

Current Research Trends in Abrasive Waterjet Machining of Fiber Reinforced Composites

The use of fiber reinforced polymer (FRP) composites in the aircraft and automotive industries exponentially. Reinforced fibers which are abrasive in nature make it hard to machine by the traditional machining. Dissipation of heat into workpiece which in turn results in enhanced cutting tool wear and damage to the workpiece is the common problems faced in traditional machining of FRPs. Nontraditional machining is favorable to reduce these issues. Abrasive waterjet machining (AWJM) is one of the best choices for machining FRPs. Development in AWJM of FRPs and the current research in this field will be discussed in details. Machining process of FRPs, quality dependents such as surface finish and variable cutting parameters will be addressed. One of main issues in AWJM noise due to high flow rate of water jet will be addressed. The importance of human safety aspects when AWJM is employed will be highlighted. Limitations and challenges in AWJM are presented elaborately.

Chapter 3 – Safety and ethics of nanotechnology

Abstract Nanotechnology is one of the ways of improving many properties of materials, including physical, chemical, physicochemical, and biological, which can be useful for various applications in biomedical, textile, aerospace, manufacturing, cosmetics, oil, defense, agricultural, and electronics industries. Nevertheless, nanotechnology products, or nanomaterials (e.g., nanotubes, nanoparticles, nanofibers, nanowires, nanocomposites, and nanofilms), can be unsafe to human health because of the way they are manipulated and treated at near atomic scale. Since these nanomaterials are produced with mainly new manufacturing techniques and have various sizes, shapes, and surface energies, they may also create some uncertainties because of the lack of specific rules and regulations governing their manufacture and manipulation. This study provides a detailed report on the safety and ethics of nanotechnology and related ethical, social, philosophical, environmental, biological, and other legal issues. The information provided here can be very useful for training and protecting scientists, engineers, students, policymakers, and regulators working in the nanotechnology and related technologies.

Abrasive waterjet machining of fiber reinforced composites: A review

Machining of fiber reinforced polymer (FRP) composites is a major secondary manufacturing activity in the aircraft and automotive industries. Traditional machining of these composites is difficult due to the high abrasiveness nature of their reinforcing constituents. Almost all the traditional machining processes involve in the dissipation of heat into the workpiece which can be resulted in damage to workpiece and rapid wear of the cutting tool. This serious issue has been overcome by water jetting technologies. Abrasive waterjet machining (AWJM) is a nontraditional method and one of the best options for machining FRPs. This paper presents a review of the ongoing research and development in AWJM of FRPs, with a critical review of the physics of the machining process, surface characterization, modeling and the newer application to the basic research. Variable cutting parameters, limitations and safety aspects of AWJM and the noise related issues due to high flow rate of water jet will be addressed. Further challenges and scope of the future development in AWJM are also presented in detail.

Graphene Thin Films on Fiber-Reinforced Epoxy Composites for Improved Fire Retardancy

Because of the high strength-to-weight and stiffness-to-weight ratios, the fiber-reinforced epoxy composites are the most common materials for many industrial applications. Nevertheless, these engineered materials can lose their properties when subjected to the high moisture, UV light and temperatures through oxidation and other decomposition processes. In order to minimize the weakness of the epoxy composites, graphene thin films were fabricated after the acid treatment process, and then applied onto the surface of fiber reinforced epoxy composites to act as heat shields. The 45 degree burn tests and surface paint adhesion tests were conducted on the prepared samples in accordance with the guidelines of the FAA Regulations, ASTM, SAE, and AMS specifications. The test results revealed significant improvements on the flame retardancy of the composites by incorporating graphene oxide thin films. Overall, this study may improve the fire resistance properties of the composites for different high temperature applications of composites.© 2014 ASME

Sustainability of fiber reinforced composites: status and vision for future

Fiber reinforced polymer (FRP) composite products offer many significant environmental benefits such as light weight, superior mechanical properties, extended service life, low maintenance and resistance to corrosion. But until now it has been difficult to compare sustainability of different FRP materials and production for processes. Concern for the environment, both in terms of limiting the use of finite resources and the need to manage waste disposal, has led to increasing pressure to recycle materials. This paper focuses on two issues that must be addressed to ensure continued growth in FRP usage is the disposal of waste generated during product manufacturing and the disposal of the products at the end of their useful life. The major cost drivers for FRPs are labor and raw materials. The use of recycled FRPS offers low-cost raw materials. This paper presents a review of the current status and outlook of FRP composites recycling and re-manufacturing techniques. A future vision for the use of FRP composites with sustainability applications is underway at many university research institutes and in industries. This paper will also state the sustainability problems of fiber reinforced composite products, and potential solutions.Copyright

Guiding the Nonmagnetic Particles by Magnetic Nanoparticles in a Microfluidic Device Using External Magnetic Fields

A microfluidic device was fabricated via UV lithography technique to separate nonmagnetic fluoresbrite carboxy microspheres (∼4.5 μm) from the ferrofluids made of magnetic nanoparticles (∼10 nm). A mixture of microspheres and ferrofluid was injected to lithographically developed Y shape micro channels, and then by applying the external magnet field, the fluoresbrite carboxy microspheres and ferrofluids were clearly separated into different channels because of the magnetic force acting on those nonmagnetic particles. During the fabrication, a number of different parameters, such as UV exposure times, UV power level and photoresist thickness were tested to optimize for our needs. In addition, in the magnetic field testing, different pumping speeds, and particle concentrations associated with the various distances between the magnet and the microfluidic system were studied for an efficient separation.Copyright