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Mechanical Engineering Laboratory 1990 March |
| 16-1 Stirring Synthesis for lntermetallic Compound Production | 
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Stirring Synthesis for lntermetallic Compound Production Intermetallic compounds have very desirable material properties, but unfortunately are very brittle when produced by conventional casting techniques. Stirring synthesis, in which the melt is stirred as it solidifies, is a new processing method which has been proposed in recent years for the production of ductile intermetallics. This research is concerned with the creation of high-performance intermetallic compounds using this technique. |
| 16-2 Application of Electromagnetic Force Transients to Powder F'orming | 
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Application of Electromagnetic Force Transients to Powder F'orming Electromagnetic techniques can be used for the generation of explosive super-high pressure transients. This has been used in the past for forming plates and tubes made from Al, Cu, and similar materials. This project aims to develop similar techniques for powder metallurgy, using hammer and sheath compaction arrangements, which have high electrical conductivity components, to transmit the pressure transient to the powder under compaction. Characteristics of these techniques are : The use of oscillating super-high pressure transients, achievement of very short compaction time, applications in producing very complex shapes, development of low cost dies. The topic of particular interest is the application to the consolidation of rapidly solidifiable and refractory powders. |
| 17-1 Computer Simulation of Metal Forming Processes | 
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Computer Simulation of Metal Forming Processes Plastic metal forming is one of today's most important materials processing technologies, but process conditions for forging, extrusion, and so on, are still largely determined empirically. This project aims to improve on this situation by developing computer programs which can simulate plastic forming processes. FEM programs are under development which can analyze deformation, stress, and strain precisely in elasto-plastic and rigid-plastic situations. Furthermore the programs which can predict changes in microstructure and strength occurring as a result of plastic deformation will be developed in the future. |
| 17-2 Near Net Shape Forging with Ceramic Dies | 
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Near Net Shape Forging with Ceramic Dies New alloys such as nickel-base superalloys and inter-metallic compounds appear to have great potential for high temperature applications, but their inherent properties make them very difficult to work. It seems that a technique known as isothermal forging might provide a solution to this problem. Using this technique, it is possible to form these difficult materials in one step, from a preform of simple shape to a near net shape final product. This research is concerned with the development of isothermal forging techniques using an industrial size (about 250mm O.D.) ceramic die which is constructed in segments. The die is made from SiAlON which can be machined into a complex shape using EDM techniques. It has been found that this type of die can be used success fully for isothermal forging in air. |
| 18-1 Advanced Surface Processing | 
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Advanced Surface Processing The aim of this work is to develop multi-function, multi-layer surface coatings which are resistant to corrosion and high temperature oxidization, which incorporate thermal and oxygen diffusion barriers, and which are durable in hostile environments up to temperatures of 2000℃. In order to achieve this, investigations are under way using various coating technologies in conjunction with treatment by a high power CO2 laser. Surface modification experiments using Excimer laser CVD are also being carried out in collaboration with industry. |
| 18-2 Fracture Mechanics of Advanced High Performance Materials for Extreme Environments | 
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Fracture Mechanics of Advanced High Performance Materials for Extreme Environments In this study, fracture mechanics and electron-microfractography are used to determine material strength and fracture characteristics at high temperature (〜2000℃) in order to establish the design concepts of high performance materials for severe environments. Analysis and monitoring techniques for characterizing damage tolerance are also under development, with a view to using them in primary structural applications. |
| 19-1 Tribotechnology for Extreme Environmental Conditions | 
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Tribotechnology for Extreme Environmental Conditions The operation of advanced machines in under extreme environmental conditions raises several tribological problems which cannot be solved using conventional lubrication technologies. For instance, there are requirements for lubricants which are stable up to 1000℃, lubricants which are contamination-free and applicable to very clean environments, lubricants which are effective even when mixed with process fluids, and tribomaterials which don't require lubricants or which can operate satisfactorily with only very thin lubricative films. This project is concerned with gaining an understanding of tribological phenomena with a view to developing the capability to find or design new high performance tribomaterials. |
| 19-2 New NDT Methods for Characterizing Surface / Subsurface Damage | 
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New NDT Methods for Characterizing Surface / Subsurface Damage The durability of materials exposed to hostile environments is closely related to the physico-chemical interactions between the surface / subsurface and the environment, and to stress concentrations around microcracks in the material. New nondestructive testing techniques are being developed to characterize these interactions in real environments. Phenomena used in these tests include: Surface phenomena associated with acoustic waves, fractoemission, luminescence, raman scattering, and infrared absorption. Research is under way towards the quantitative application of these test methods to micro and macro engineering systems. |
