1/2015
Budai D.; Tisza M.:
Development trends in aluminium car body production 5
Application of aluminium parts in automotive industry seems to be the most important possibility in mass decreasing, however manufacturers having much experience in steel processing find much difficulty when aluminium should be formed or welded. Researchers expect the most favourable results from high temperature and high velocity deformation.
Hajdú S.; Czibere T.; Kalmár L.:
Starting behaviour of cross flow turbine 11
Authors summarise the main operation characteristics of the cross flow tur-bines. They discuss some processes (among them the starting one) to be de-veloped in order to improve the investigated turbine applicability. In spite of its simplicity the applied model gives possibility to draw important conclusions.
Ecsedi I.; Baksa A.:
Stress analysis of rotating disk reinforced by a ring on its boundary 15
Paper deals with the stress analysis of rotating elastic disk reinforced by an elastic ring on its cylindrical boundary surface. Formulae of stresses and radial displacement are derived and the critical value of angular velocity is also de-termined.
Farkas J.; Jármai K.:
Comparison of welded structures optimized for minimum volume and cost 19
After elaboration of the structure optimisation for minimum volume authors de-rived a new method of optimization for manufacturing cost. Application of dif-ferent object functions gives little difference in case of simple structures, but much more in complex ones.
Krámer Gy.; Siménfalvi Z.; Szepesi L. G.:
Method for calculation of effectiveness and heat-request of ammonia-water based absorption cooling system 24
Paper shows a method for calculations and estimations of the effectiveness and heat request of the absorption refrigeration systems. Authors wanted to eliminate the use of complex databases and expensive professional software. In calculation procedure authors use thermal constants described in a former study.
Marosné Berkes M.; Szilágyiné Biró A.; Lőrincz A.; Koncsik Zs.:
Application of scratch test in the qualifying process of gas nitrided surface layer of steels 28
Using low alloyed steel (51CrV4) suitable for Q+HTT heat treating, carbonitrid-ed layers were produced by different holding temperature and time. For qualify-ing purpose of the surface layer authors advise not only the traditional hard-ness test and optical microscopic examination but a newly developed scratch test method as well.
Rádics J. P.; Jóri J. I.; Fenyvesi L.:
Validation of soil CO2 emission model using non-linear regression analysis 36
Emission model elaborated by authors and the applied non-linear regression analysis theory make the estimation of the gas emission of soils possible. The derived model is suitable for comparison of carbon dioxide emission obtained after use of different tillage processes and machines.
