J. Jaworski, T. Trzepieciński: Faculty of Mechanical Engineering and Aeronautics, Rzeszow University of Technology, Rzeszów, Poland This paper presents the results of research on the determination of the coefficient of thermal conductivity and hot hardness of cutters made of selected grades of low-alloy high-speed steels, HS 6-5-2 and HS3-1-2. The investigations of hot hardness and yield stress...

Power transformers represent the largest portion of capital investment in transmission and distribution substations. In addition, power transformer outages have a considerable economic impact on the operation of an electrical network. One of the most important parameters’ governing a transformer’s life expectancy is the hot-spot temperature value. Due to under estimation of stray losses in powe...

this research was conducted to study the effect of lime based flux with the composition of cao-20%caf2-8%feo on simultaneous removal of phosphorus and sulfur from hot metal. the effects of na2o and oxygen blowing were also studied. the experiments were performed using an induction furnace and hot metal produced in isfahan steel company in the temperature range 1350-1450 ºc. the results showed t...

this paper modeled heating air of a room through examining free convection in a 3d chamber. the chamber had cold and hot sources with tc and th temperatures, respectively. its other walls were adiabatic. this study aimed at predicting effect of temperature difference, displacement of hot and cold sources and their aspect ratio on flow field, temperature and heat transfer rate. to conduct the st...

During the past several decades, observational data have shown a faster increase in hot temperature extremes than the change in mean temperature. Increasingly high extreme temperatures are expected to affect terrestrial ecosystem function. The ecological impact of hot extremes on vegetation production, however, remains uncertain across biomes in natural climatic conditions. In this study, we in...

Deuterated oxides exhibit prolonged hot carrier lifetimes at room temperature. We report evidence that this improved hot carrier hardness exists over the temperature range between -25 °C and 200 °C. However, the benefit of deuterium incorporation deceases with increasing stress temperature. Furthermore the VT -shift shows a remarkable absence of temperature dependence for the deuterated samples...

The effect of spin mixing due to thermal spin waves and temperature dependence of hot electron spin polarization to the collector current in a spin-valve transistor has been theoretically explored. We calculate the collector current as well as the temperature dependence of magnetocurrent at finite temperatures to investigate the relative importance of spin mixing and hot electron spin polarizat...

Hot-electron transport and microwave noise are investigated for n-type 4H–SiC (n = 2 × 10 cm−3) subjected to a pulsed electric field applied parallel to the basal plane. At room temperature, the negative differential conductance, masked by field ionization at the highest fields, is observed in the field range between 280 and 350 kV/cm. The threshold fields for the negative differential conducta...

Hot torsion test (HTT) has extensively been used to analysis and physically model flow behavior and microstructure evolution of materials and alloys during hot deformation processes. In this test, the specimen geometry has a great influence in obtaining reliable test results. In this paper, the interaction of thermal-mechanical conditions and geometry of the HTT specimen was studied. The commer...

Transfer table is an essential stage between roughing and finishing rolling stands in a hot-strip rolling mill. High temperature and long time that strip is exposed to air at this stage cause a considerable heat loss that accounts for uneven temperature distribution, non-uniform surfaces, reduced product quality and increased production costs. Using thermal shields on the transfer table is cons...