Refining and Casting of Steel

Steel has become the most requested material all over the world during the rapid technological evolution of recent centuries. As our civilization grows and its technological development becomes connected with more demanding processes, it is more and more challenging to fit the required physical and mechanical properties for steel in its huge portfolio of grades for each steel producer. It is necessary to improve the refining and casting processes continuously to meet customer requirements and to lower the production costs to remain competitive. New challenges related to both the precise design of steel properties and reduction in production costs are combined with paying special attention to environmental protection. These contradictory demands are the theme of this book

NDE: An effective approach to improved reliability and safety. A technology survey

Technical abstracts are presented for about 100 significant documents relating to nondestructive testing of aircraft structures or related structural testing and the reliability of the more commonly used evaluation methods. Particular attention is directed toward acoustic emission; liquid penetrant; magnetic particle; ultrasonics; eddy current; and radiography. The introduction of the report includes an overview of the state-of-the-art represented in the documents that have been abstracted

Toward a rigorous derivation of a stable and consistent smoothed particle hydrodynamics method

The aim of this thesis is to provide an investigation toward a rigorous derivation of a stable and consistent numerical method based on the established Smoothed Particle Hydrodynamics method. The method should be suitable for modelling the large deformation transient response of fluids and solids, the interests of the Crashworthiness, Impact and Structural Mechanics group (CISM) at Cranfield University. A literature review of the current state of the art of the SPH method finds that the conventional SPH equations are not derived in a rigorous way, often the equations are manipulated into a mathematically equivalent form in order to preserve conservation of linear momentum, which often leads to different results; the reasons for this are unknown and it is not fully understood how each particular form of the discrete equations effects the solution in terms of stability, accuracy and convergence. This leads to specific objectives being defined which underpin the overall aim of the thesis. The first objective is to develop an understanding of the SPH method and the implementation used at Cranfield University, this is done through a capability study which demonstrates the coupled SPH-FE method and a number of relevant improvements to the MCM code including the addition of a turbulence model and the modification of the SPH contact algorithm to model lateral forces between materials. This is demonstrated through the implementation of a friction model, which suggests that the contact algorithm is suitable for resolving lateral forces based on the relative velocity between materials, with the potential for coupling with a structural FE model ... [cont.]

Hybrid Bulk Metal Components

In recent years, the requirements for technical components have steadily been increasing. This development is intensified by the desire for products with a lower weight, smaller size, and extended functionality, but also with a higher resistance against specific stresses. Mono-material components, which are produced by established processes, feature limited properties according to their respective material characteristics. Thus, a significant increase in production quality and efficiency can only be reached by combining different materials in a hybrid metal component. In this way, components with tailored properties can be manufactured that meet the locally varying requirements. Through the local use of different materials within a component, for example, the weight or the use of expensive alloying elements can be reduced. The aim of this Special Issue is to cover the recent progress and new developments regarding all aspects of hybrid bulk metal components. This includes fundamental questions regarding the joining, forming, finishing, simulation, and testing of hybrid metal parts

Autonomous Scale Car Using Computer Vision and Neural Networks

This report explores the feasibility of creating an autonomous 1:10 scale car capable of racing against RC cars on any indoor track. Custom made and equipped with a livestream sensor display module, the car leverages Artificial Neural Networks (ANN) to produce optimal driving outputs. Manipulating grayscale pixel input from a single, front-facing camera, the car navigates without the use of mapping or localization. Instead, the car relies on extensive training that allows the vehicle to adapt to variable conditions

Marshall Space Flight Center Research and Technology Report 2019

Today, our calling to explore is greater than ever before, and here at Marshall Space Flight Centerwe make human deep space exploration possible. A key goal for Artemis is demonstrating and perfecting capabilities on the Moon for technologies needed for humans to get to Mars. This years report features 10 of the Agencys 16 Technology Areas, and I am proud of Marshalls role in creating solutions for so many of these daunting technical challenges. Many of these projects will lead to sustainable in-space architecture for human space exploration that will allow us to travel to the Moon, on to Mars, and beyond. Others are developing new scientific instruments capable of providing an unprecedented glimpse into our universe. NASA has led the charge in space exploration for more than six decades, and through the Artemis program we will help build on our work in low Earth orbit and pave the way to the Moon and Mars. At Marshall, we leverage the skills and interest of the international community to conduct scientific research, develop and demonstrate technology, and train international crews to operate further from Earth for longer periods of time than ever before first at the lunar surface, then on to our next giant leap, human exploration of Mars. While each project in this report seeks to advance new technology and challenge conventions, it is important to recognize the diversity of activities and people supporting our mission. This report not only showcases the Centers capabilities and our partnerships, it also highlights the progress our people have achieved in the past year. These scientists, researchers and innovators are why Marshall and NASA will continue to be a leader in innovation, exploration, and discovery for years to come

Phase stability in steels under electropulsing

There are increasing interests to alternate the microstructure and hence the properties of steels that are applied in various environment conditions using a work-efficient and energy-saving manner. The desirable microstructure evolution is often not achievable by means of conventional thermo-mechanical processing and solid-state phase transition. This thesis has considered four fundamental engineering problems, namely (i) the possibility of anti-aging processing for the aged steels in service at high temperature, (ii) the recovery of the lost strength for the steels at high temperature, (iii) the suspension of crack initiation and propagation during cold-working of steels with eutectoid microstructures and (iv) the regaining of strength during tempering of a steel containing martensite. Phase stability in the processing environment is the primary concern in each of the list problems because it presents, in thermodynamically, the possibility to achieve the goals using the designed processing. Electropulsing processing has been considered and integrated with the conventional thermomechanical processing in the development of this PhD thesis. The so-called electropulsing treatment utilises electric current pulses with high peak current density and short pulse duration. Due to the nature of the short duration pulse, the energy consumption is very low. The high current density enables a very strong impact of electropulsing on the microstructure evolution and hence is work efficient. Following results have been obtained through the study： • Using the appropriate electropulsing parameters, the formed secondary phase (e.g. χ-phase) by precipitation in 316L stainless steels at elevated temperature can be dissolved. Electropulsing processing can supress the precipitation and homogenize the alloying elements in the stainless steel. The stability of the secondary phases in the stainless steel has been changed by the imposed electropulse. • Electropulsing treatment is able to alternate the delta-ferrite phase transition. This has been proved in the treatment of 2205 duplex stainless steel. The new format of phase transition causes strengthening of the steel at high temperature. The stability of phases in the steel has been affected by the applied electropulsing treatment. • For the light steels containing high aluminium composition, electropulsing is able to affect the thermodynamic stability and grain morphology of κ-carbide. This leads to significant improvement of steel formability. • Application of electropulsing processing to dual-phase automotive steel changes the stability of martensite phase. The processing improve the mechanical properties and refined the microstructure of this steel. The fundamental understanding of the experimental observations has been developed based on the thermodynamic and kinetic analysis.Open Acces