Determination of Transformation Induced Heat Transfer Coefficients in Mechanical Properties of Powder Metallurgy Steels
2 Abstract: Powder metallurgy has been used for the manufacture of fully dense, which have not reacted composites consisting of a matrix of copper containing 50 -60 vol% particles with negative thermal ZrW2O8 expansion. On cycling between 25 and 300°C, the compounds showed coefficients thermal expansion which varies rapidly with temperature and significantly larger than expected by theory. Improvements in adhesion strength and thermal properties of composite materials have been achieved in atomized copper alloy with small additions of chromium to increase the interfacial bonding in composite Cu / diamond from a nano-sized thin Cr3C2layer.
Fabrication and characterization of americium, neptunium and curium bearing MOX fuels obtained by powder metallurgy process
MOX fuel pellets containing up to 1.4 wt% of Minor Actinides (MA), i.e. Am, Np and Cm, were fabricated to demonstrate the technical feasibility of powder metallurgy process involving, pelletizing and sintering in controlled atmosphere. The compounds were then characterized using XRD, SEM and EDX/EPMA. Dense pellets were obtained which closed porosity mean size is equal to 7 μm. The results indicate the formation of (U, Pu)O2 solid solution. However, microstructure contains some isolated UO2 grains. The distribution of Am and Cm appears to be homogeneous whereas Np was found to be clustered at some locations.
A new method for evaluation of friction in bulk metal forming
Abstract In this investigation a simple theoretical analysis of the cylindrical compression test has been developed so that the constant friction factor can be estimated quantitatively by using cold/hot compression test. The compression tests have been carried out on the Ti-IF-steel without lubricant, with mica sheets and with glass powder lubricants the commercial aluminum with oil lubricant to confirm this analysis. This new method for obtaining the constant friction factor may be called “The Barrel Compression Test”. The advantages of the proposed method are: (i) very simple method, (ii) high sensitivity of geometrical shape of cylinder to friction condition, (iii) does not need force measurement, and (iv) the constant friction factor can be determined for forming processes corresponding to actual processing condition.