Recovery of Short Circuit Current of 3J Solar Cells by Current Injection at Low Temperature
InGaP/GaAs/Ge triple-junction (3J) solar cells designed for space applications were irradiated with 10 MeV protons at 3times1013 /cm2 at 210 K. Current at 0.25 A/cm2 was injected into the irradiated 3J solar cells after irradiation at 210 K to avoid the thermal annealing effects. The short circuit current (Isc) recovered with increasing current injection time, and the recovery saturated at current injection times above 1000 sec. The saturated Isc was 98% of the initial value. The defect annealing rate (A) was estimated to be between 0.003 and 0.01/s from the fitting of the current injection time dependence of the recovery of I sc
Radiation Resistance of InP-Related Materials
Irradiation effects of 1-MeV electrons on InP-related materials such as InP, InGaP and InGaAsP have been examined in comparison with those of GaAs. Superior radiation-resistance of InP-related materials and their devices compared to GaAs has been found in terms of minority-carrier diffusion length and properties of devices such as solar cells and light-emitting devices. Moreover, minority-carrier injection-enhanced annealing of radiation-induced defects in InP-related materials has also been observed.
Numerical Simulation of Induction Heating Process of Continuous Casting Slab
Compared with traditional blazing furnace, the Continuous Casting-Direct Rolling is an advanced manufacturing steel technology, which can reduce energy waste, decrease pollution and enhance efficiency. The characteristics of steels during induction heating are complex, the change of material properties with temperature makes exact analysis methods very difficult to implement. Therefore, a powerful computer aided numerical tool (i.e., finite difference analysis) is selected to numerically model the induction heating process in this paper. The mathematic model coupling with electromagnetic field and thermal field was established, and it was solved by finite difference method (FDM), thus the slab temperature distribution and its variation with time were obtained, and the characteristics in whole induction heating process were studied. To validate the program feasible, the results were evaluated and compared with experiment results, which showed that the simulation results are reliable and effective. The skin effect in heating process from the two results was studied and demonstrated, the temperature change caused by different parameters such as the induced power intensity and the corner radian were also presented, which indicate that the slab temperature can be heated uniformly through adjusting these parameters, thus the continuous casting slab can meet the rolling requirement.