查看更多>>摘要：Isothermal forming is done, at hot workingtemperatures without increase or decrease in temperature ofworkpiece, by maintaining the tooling at a proper temperature. Itensures optimum utilisation of speed and high quality ofcomponents. A short overview of the technique is attempted here for steels.
查看更多>>摘要：This paper highlights the aspects of peroxideformation on the surfaces of metallic origin, during the formativestages of oxide corrosion products. It is argued that oxygen inOH~(-) ions, in presence of photonic fluxes, motivate the OH~(-)ions to interact with each other electrocatalytically, formingH_2O_2 on selective metallic sites and the peroxides formedperforms the function of a convenient surface oxidizers. It isfurther argued that in ambient air corrosion, the peroxides may beeffective during the formative stages of surface deterioration,where energy barriers are to be crossed. The hypothesis has beensupported by a set of experimental test results.
查看更多>>摘要：In the die and mould making industry it is commonto hand polish the part as a finishing operation irrespective of thetype of primary machining process used in manufacture (e.g.milling, electro discharge machining, etc.).However, there are many problems which are associated with handpolishing (also known as lapping). Thus a possible alternativewhen die sinking using Electro Discharge Machining (EDM) is toelectrochemically polish the surface. Hence the surface resultingafter the EDM process will be a combination of twoabovementioned processes, and as a consequence the way in whichthey interact with each other.The aim of this paper is to examine how two different polishingprocesses, namely, manual lapping and electrochemical polishingaffect the microstructure and the surface topography of the EDMsurface, and also which surface parameters best represent thedifference between the two secondary processes.
查看更多>>摘要：Recently spray coating had come in the limelight ofEngineering Industries. As these coatings do not require any wetenvironment, as in the case of electroplating, phosphating, etc.Spraying may be conducted by thermal processes and also byplasma processes. Both the routes have their specific advantagesand disadvantages. However spraying being a dry process appearsto be environment friendly.This paper has discussed two specific case studies respectively inthe field of thermal spraying and plasma spraying. It appears thatthermally sprayed aluminium surface may be made resistant tocorrosion by increase of layer thickness, but, plasma sprayedcoating does not respond to that extent, as a result of increase oflayer thickness.
查看更多>>摘要：Experimental test data on stabilization of thesurface-films in protic media (in moderately high pH environment)both in presence and absence of photonic- fluxes, have beenpresented in this paper, using substrates like particulated Cu60,Zn40 brass and 304 ss substrate. Data have also been collected onthe above substrates, in aprotic environment like ambient dry-airThe role of oxygen in both the dry air and OH~(-) ions in the proticmedium have been highlighted, furnishing an innovative model ofsurface protection.
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