There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

비만아 부모의 돌봄 경험: q 방법론

A review on selective laser sintering/melting (SLS/SLM) of aluminium alloy powders: Processing, microstructure, and properties

A review of selective laser melting of aluminum alloys: Processing, microstructure, property and developing trends

Friction stir welding (FSW) is a widely used solid state joining process for soft materials such as aluminium alloys because it avoids many of the common problems of fusion welding. Commercial feasibility of the FSW process for harder alloys such as steels and titanium alloys awaits the development of cost effective and durable tools which lead to structurally sound welds consistently. Material selection and design profoundly affect the performance of tools, weld quality and cost. Here we review and critically examine several important aspects of FSW tools such as tool material selection, geometry and load bearing ability, mechanisms of tool degradation and process economics.

Review: friction stir welding tools

Friction stir welding/processing of metals and alloys: A comprehensive review on microstructural evolution

The friction stir welding (FSW) technique is widely accepted to be one of the most significant welding techniques to emerge in the last 20 years. Friction stir welding of Al-alloys is now commonplace and is covered in several recent reviews, including one in this journal. Consequently, the technique is currently being used for joining of these alloys in various industrial applications. Complementary to these developments has been a dramatic increase in research into joining of other alloys and systems by FSW. This field is very active, but less mature. Thus, the aim of this review article is to build on our understanding of the fundamentals, as applied to Al-alloys that laid out in the previous review in this journal, and to address the current state-of-the-art of FSW developing beyond Al-alloys, including Mg-alloys, Cu-alloys, steels, Ti-alloys and metal matrix composites, focusing particularly on microstructural aspects, including texture formation, and the resulting properties of these joints. ...

Friction stir welded structural materials: beyond Al-alloys

The diversity and never-ending desire for a better life standard result in a continuous development of the existing manufacturing technologies. In line with these developments in the existing production technologies the demand for more complex products increases, which also stimulates new approaches in production routes of such products, e.g., novel welding procedures. For instance, the friction stir welding (FSW) technology, developed for joining difficult-to-weld Al-alloys, has been implemented by industry in manufacturing of several products. There are also numerous attempts to apply this method to other materials beyond Al-alloys. However, the process has not yet been implemented by industry for joining these materials with the exception of some limited applications. The microstructures and mechanical properties of friction stir welded Al-alloys existing in the open literature will be discussed in detail in this review. The correlations between weld parameters used during FSW and the microstructures evolved in the weld region and thus mechanical properties of the joints produced will be highlighted. However, the modeling studies, material flow, texture formation and developments in tool design are out of the scope of this work as well as the other variants of this technology, such as friction stir spot welding (FSSW).

Recent Developments in Friction Stir Welding of Al-alloys

The mass saving potential of light-weight materials, such as Al alloys, is beneficial for fuel economy and reducing CO2 emissions. However, the wide-spread use of these alloys has been long hindered due to the difficulty in fusion joining as well as their high cost. Welding of Al alloys, which are considered to be difficult to weld through conventional arc welding, is now possible by either of low heat input arc welding, high-power density fusion joining, such as laser beam welding and electron beam welding, or friction stir welding. Particularly, friction stir welding can be successfully applied to these materials owing to the fact that no melting takes place in the weld nugget. The aim of this overview is to summarize the developments in the joining of Al alloys over the recent years. This study is also intended to provide guidance for the industry and researchers dealing with joining of these alloys.

Recent developments in joining of aluminum alloys

Advanced materials generally require novel joining techniques. Developments in new materials research should be conducted hand in hand with work on weldability and joining capacity aspects. Sound joint quality for any new material has always been considered a milestone in a research and development scheme for a new material, particularly in terms of widespread applications. Better understanding of the microstructure-mechanical properties relationships of the bonded or welded joints will feed back to the materials development activities both in conventional and new materials areas. The two joining processes diffusion bonding and laser welding are considered in this literature review, since these processes are capable of joining a wide range of materials of interest in the aerospace industry, as well as in many other industrial applications, and offer remarkable advantages over conventional fusion welding processes. Of particular interest is the ability to join the more difficult aerospace alloys wi...

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Papers

Friction stir welding/processing of metals and alloys: A comprehensive review on microstructural evolution

Friction stir welded structural materials: beyond Al-alloys

Recent Developments in Friction Stir Welding of Al-alloys

Recent developments in joining of aluminum alloys

Progress in joining of advanced materials