摘要:

Precipitation of interstitial loops and iron nitride in an iron nitrogen alloy, has been examined in the temperature range 30 °C to 300 °C using a High Voltage Electron Microscope. The use of thick foils has enabled the direct observation of iron nitride precipitation. Observations confirm both theoretical and indirect experimental studies of the hardening behaviour of α-iron alloys following neutron irradiation.

ISSN:0033-7579    

DOI:10.1080/00337577208231228

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

The creep ductility of Magnox AL80 (Mg/0.8 wt per cent A1/0.005 wt per cent Be) fuel element cans is known to decrease with increasing irradiation. A possible cause of this embrittlement is void nucleation at inert gas bubbles formed on grain boundaries. The necessary size and spacing of these bubbles are calculated together with the total number of gas atoms which they must contain. The numbers of inert gas atoms arising from the following processes are also calculated: (a) the lithium (n, α) reaction, (b) the injection of fission fragments into the can, (c) fission of plutonium which has diffused into the can. Each mechanism can produce more than the theoretical minimum quantity of gas to account for the observed embrittlement. However, the appropriate grain boundary distribution of gas is unlikely to arise from (b) and (c) and the quantity from (a) exceeds the minimum only slightly, even if all the gas is in bubble nuclei. The need for continued control over the lithium content of the canning stock material is emphasized. It is demonstrated that greater plutonium penetration could cause extensive embrittlement of a Magnox ZR55 (Mg/0.55 wt per cent Zr) alloy can.

ISSN:0033-7579    

DOI:10.1080/00337577208231229

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

During irradiation, fast neutrons produce regions depleted of atoms. It is believed that these regions are responsible for most of the hardening observed after neutron irradiation. The present paper discusses the dissolution of the depleted zones during a post-irradiation anneal and the subsequent recovery of the yield strength. The zones dissolve by emitting vacancies and therefore have an activation energy made up of the sum of the vacancy binding energy to the zone and the vacancy migration energy. The resultant activation energy increases with recovery. For zirconium base alloys it was found that the activation energy varies from 49,700cal/mole at 10 per cent recovery to 61,600 cal/mole at 50 per cent recovery. Experimental data available indicate a similar increase in the activation energy with recovery.

ISSN:0033-7579    

DOI:10.1080/00337577208231230

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

The gamma irradiation damage in silicon has been extensively studied by many investigators.(1–6)However, little has been reported about the effects of radiation on the current-voltage (I–V) characteristics of silicon, particularly of high-resistivity silicon at radiation temperatures other than the room temperature. This paper is a report of some new results on the I–V characteristics of low and high resistivity silicon before and after gamma irradiation at the temperature of 38 °C and −196 °C.

ISSN:0033-7579    

DOI:10.1080/00337577208231231

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor

摘要:

In these experiments we have measured the recovery spectra of the electrical resistivity after neutron irradiation at 78 °K of previously cold-worked copper specimens at room temperature and compared with well annealed specimens after neutron irradiation.

ISSN:0033-7579    

DOI:10.1080/00337577208231232

出版商:Taylor & Francis Group    

年代:1972

数据来源: Taylor