The operating principle of electron beam machining (EBM) is that a high velocity electron beam is made to impinge on the surface of the work piece to be machined. The electrons are accelerated to velocities as high as half the velocity of light. On impact of electrons with the work piece, their kinetic energy is converted into thermal energy which melts and vaporises the metal.
(Juneja, B. L., Sekhon, G. S., Seth, N., Fundamentals of Metal Cutting and Machine Tools, 2nd Ed, p. 288)
Chemical Machining (March 28, 11:01):
Chemical machining or chemical milling is a process used to dissolve the workpiece material in chemical solutions. Since the chemical solutions used have the ability to dissolve all of the workpiece material, the parts which are not to be dissolved would have to be applied with a mask which resists the chemical action of the solution, so that only the unmasked portion gets removed by the chemical solutions.
(Manufacturing Technology, Metal Cutting & Machine Tools, McGraw-Hill, p. 293)
Liquid Phase Sintering (March 28, 16:10):
Liquid phase sintering is a subclass of the sintering process and can be defined as sintering involving a coexisting liquid and particulate solid during some part of the thermal cycle. The most common way to obtain the liquid phase is to use a system involving a mixture of two powder metals in which there is difference in the melting temperatures between the metals. The interaction of two powders leads to formation of a liquid during sintering. The melted metal thoroughly wets the solid particles' leading to rapid consolidation and giving rapid compact densification without the need for an external force. It is' of course' essential to restrict the amount of liquid phase in order to avoid impairing the shape of the part; Depending on the metals prolonged heating may lead to diffusion of the liquid metal into the solid or the dissolution of solid particles into the liquid melt. In either case' the resulting part is fully dense (having no pores) and strong.
(Vukota Boljanovic, PH. D., Metal ShapingProcesses: Casting and Molding, Particulate Processing, Deformation Processes, Metal Removal, p. 96)
Abrasive Flow Machining (March 30, 18:57):
Abrasive flow machining (AFM) is an innovative finishing and polishing operation with a gentle material removal mechanism. In contrast to other machining methods for deburring and polishing, it is possible to machine difficult-to-access cavities, inner contours and undercuts in a reproductible manner. Typical components that could be machined by AFM are extrusion and compression molding dies as well as crimping and stamping tools. Use of AFM on these tools showed that within 2 minutes processing time an improvement of the surface roughness from Ra=2µm to Ra=0.2µm could be achieved.
(Aurich, J. C., Dornfeld, D., Burrs - Analysis, Control and Removal, p.73)
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