Experimental Study of Upsetting and Die Forging with Controlled Impact
The results from experimental research of deformation by upsetting and die forging of lead specimens wit controlled impact are presented. Laboratory setup for conducting the investigations, which uses cold rocket engine operated with compressed air, is described. The results show that when using controlled impact is achieving greater plastic deformation and consumes less impact energy than at ordinary impact deformation process. Keywords—Rocket Engine, Forging Hammer, Sticking Impact, Plastic Deformation.
InterCriteria Decision Making Approach for Metal Chips Briquetting
In the presented paper for the analysis purposes we have used experimental results of impact briquetting of grey cast iron chips. The presented multicriteria decision making method is based on two fundamental concepts: intuitionistic fuzzy sets and index matrices. We have named it ‘InterCriteria’ decision making approach, which utilizes the apparatus of index matrices and intuitionistic fuzzy sets takes an existing multiobject multicriteria evaluation table and generates a new table that contains estimations of the pairwise relations among the set of evaluating criteria. Our goal is to increase the efficiency of the process of briquetting metal chips with good density and quality.
Phase characterisation of simulated high burn-up UO2 fuel
Abstract To determine the lattice constant variation with burn-up and the oxidation behaviour at high temperatures, simulated UO2-spent fuels with burn-ups up to 200 GWd tM−1 were prepared by cold pressing and sintering and characterised by X-ray diffraction analysis and thermogravimetry. The fcc-lattice parameter of the sintered samples determined at room temperature, showed a continuous decrease with the simulated burn-up. During oxidation the conversion of the simulated fuels to the (U,FP)4O9 and (U,FP)3O8-type phases was strongly delayed when the simulated burn-up exceeded 80 GWd tM−1. Also, at high burn-ups (>100 GWd tM−1), large fractions of the (U,FP)4O9-type phase remained untransformed to (U,FP)3O8 after prolonged exposure to air at 950–1000°C. This suggests a marked widening of the (U,FP)4O9-phase field when the amount of substituted uranium atoms exceeds values of about 8%.