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Brotzen, F. R.

Publications and source records attributed to Brotzen, F. R..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Notch sensitivity of hydrogenated oxygen-strengthened titanium

While earlier studies have shown that the tensile properties and fracture test intensity factors of oxygen-strengthened Ti remain nearly unaffected by the presence of about 70 ppm (weight) hydrogen, the Charpy V-notch test-determined impact properties of oxygen-bearing Ti are strongly affected by the presence of hydrogen. The present study establishes that, concurrently with the strengthening effect of oxygen, there is a substantial lowering of ductility. The presence of hydrogen has virtually no effect on the notch strength of Ti alloys of either low or high oxygen content, where hydrogen contents lie in the 25-80 range.

Wasz, M. L.↗
NASA NTRS1990

The fast diffusion of Au IN Pb

A treatment of the phenomenon of fast diffusion in lead is presented. The model used is based upon the fast diffusion of free solute interstitials. The very large negative enhancement coefficients found in the Pb-(Au, Ag) systems is explained by the formation of first and second order clusters of vacancies and substitutional solute atoms.

Mclellan, R. B.↗
NASA NTRS1990

The effect of hydrogen on the fracture toughness of oxygen-strengthened titanium

Studies of oxygen-strengthened titanium alloys have indicated that while hydrogen has little effect on tensile properties, it causes a marked decrease in impact strength. It is presently established experimentally that the presence of hydrogen has essentially no effect on the fracture-toughness factor at the onset of crack propagation, in commercial-grade titanium alloys containing either low or high concentrations of oxygen. These findings are congruent with other study results on the tensile properties of these alloys, but contrast with the previously noted pronounced effect of hydrogen on impact resistance.

Wasz, M. L.↗
NASA NTRS1989

The effect of hydrogen on mechanical properties of oxygen-strengthened titanium

The effect of oxygen on the hydrogen embrittlement in titanium was investigated in two Ti-based alloys containing different amounts of oxygen: 0.064 and 0.154, in wt pct. Tensile, impact, and hardness tests were performed with and without prior hydrogenation of the specimens. Results show that, while the presence of hydrogen, even in relatively small amounts, will not affect the hardness or room-temperature tensile properties determined at relatively slow strain rates, hydrogen will reduce significantly the impact resistance, as determined by the Charpy V-notch test. This deleterious effect on the impact resistance was found to be exacerbated by an increase of oxygen in the alloy.

Wasz, M. L.↗
NASA NTRS1971

Stress corrosion in titanium alloys and other metallic materials

Multiple physical and chemical techniques including mass spectroscopy, atomic absorption spectroscopy, gas chromatography, electron microscopy, optical microscopy, electronic spectroscopy for chemical analysis (ESCA), infrared spectroscopy, nuclear magnetic resonance (NMR), X-ray analysis, conductivity, and isotopic labeling were used in investigating the atomic interactions between organic environments and titanium and titanium oxide surfaces. Key anhydrous environments studied included alcohols, which contain hydrogen; carbon tetrachloride, which does not contain hydrogen; and mixtures of alcohols and halocarbons. Effects of dissolved salts in alcohols were also studied. This program emphasized experiments designed to delineate the conditions necessary rather than sufficient for initiation processes and for propagation processes in Ti SCC.

Harkins, C. G.↗
NASA NTRS1971

Ordering in CuAu

Rapidly quenched CuAu ordered state development on low temperature annealing, presenting Young modulus variation as function of heat treatment time

Brotzen, F. R.↗