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Herbell, T. P.

Publications and source records attributed to Herbell, T. P..

32 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Thermogravimetric study of the reduction of oxides of nickel and chromium

The controlled hydrogen, carbon, and hydrogen-carbon reductions of the oxides of nickel and chromium were evaluated by thermogravimetric means. The materials studied were nickel (nickelous) oxide (NiO) and chromic sesquioxide (Cr2O3), mixed NiO-Cr2O3, and oxidized nickel - 20-percent chromium (Ni-20Cr). NiO was effectively reduced by all three atmospheres, Cr2O3 only by hydrogen-carbon, NiO-Cr2O3 by hydrogen and hydrogen-carbon, and oxidized Ni-20Cr by hydrogen and hydrogen-carbon and to a considerable extent by carbon alone. The results suggest that the presence of nickel promotes the reduction of Cr2O3. However, no definite explanation could be reached for the effectiveness of the hydrogen-carbon reduction of Cr2O3.

Herbell, T. P.↗
NASA NTRS1973

Thermogravimetric study of the reduction of oxides of nickel and chromium

The effectiveness of hydrogen, carbon and hydrogen-carbon in reducing NiO, Cr2O3, mixed NiO-Cr2O3 and oxidized Ni-20Cr was evaluated by thermogravimetry. NiO was effectively reduced by all three atmospheres, Cr2O3 only by hydrogen-carbon, NiO-Cr2O3 by hydrogen and hydrogen-carbon and oxidized Ni-20Cr by hydrogen, hydrogen-carbon and partially by carbon alone. The results indicate that nickel and carbon promote the reduction of Cr2O3.

Herbell, T. P.↗
NASA NTRS1972

Thermogravimetry system designed for use in dispersion strengthening studies.

A thermogravimetry system, designed to study the reduction of oxides in metal and alloy powders to be used in dispersion strengthened materials, is described. The apparatus was devised for use at high temperatures with controlled atmospheres. Experimental weight change and moisture evolution results for the thermal decomposition of calcium oxalate monohydrate in dry helium, and experimental weight change results for the reduction of nickel oxide in dry hydrogen and hydrogen containing 15,000 p.p.m. water vapor are presented. The system is currently being successfully applied to the evaluation of the reduction characteristics and the removal of impurities from metals and alloys to be used for dispersion strengthening.

Herbell, T. P.↗
NASA NTRS1972

Thermogravity system designed for use in dispersion strengthening studies

A thermogravimetry system designed to study the reduction of oxides in metal and alloy powders to be used in dispersion strengthened materials is described. The apparatus was devised for use at high temperatures with controlled atmospheres. Experimental weight change and moisture evolution results for the thermal decomposition of calcium oxalate monohydrate in dry helium, and experimental weight change results for the reduction of nickel oxide in dry hydrogen and hydrogen containing 15,000 PPM water vapor are presented. The system is currently being successfully applied to the evaluation of the reduction characteristics and the removal of impurities from metals and alloys to be used for dispersion strengthening.

Herbell, T. P.↗
NASA NTRS1972

Hydrogen halide cleaning of powder metallurgy nickel-20 chromium-3 thoria.

The Cr2O3 content of powder metallurgy nickel-20 chromium-3 thoria was reduced with atmospheres consisting of hydrogen plus hydrogen chloride (HCl) or hydrogen bromide (HBr). The nonthoria oxygen content or 'oxygen excess' was reduced from an initial amount of greater than 50,000 ppm to less than 100 ppm. Low temperatures were effective, but lowest oxygen levels were achieved with the highest cleaning temperature of 1200 C.

Herbell, T. P.↗
NASA NTRS1967

Gas purged dry box glove Patent

Gas purged dry box glove reducing permeation of air or moisture into dry box or isolator by diffusion through glove

Herbell, T. P.↗
NASA NTRS1965

Double gloves reduce contamination of dry box atmosphere

Pair of encased low permeability hand gloves between which an inert gas circulates reduces dry box contamination. This innovation is applicable to dry boxes using radioactive and alkali metal compounds, submicron powders, and liquid metals.

Herbell, T. P.↗