Materials and mechanics of rate effects in brittle fracture. Progress report, October 1979-October 1980

ABSTRACTThe effect of strain rate on hydrogen embrittlement of low alloy 4340 steel was studied using double-notched tensile samples electrochemically charged in-situ with hydrogen in 1N H2SO4 + 5 mg/l As2O3 solution. The mechanical response of samples with prior austenitic grain sizes of 10 and 40 μm and martensitic hardness of 43-52 HRC were examined after hydrogen charging times of 0-20 min. Increasing the strain rate for hydrogen charged samples resulted in decreased failure strains and increased evidence of brittle fracture. Brittle fracture surfaces for the harder samples showed primarily intergranular fracture while softer samples exhibited predominantly quasi-cleavage.

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Spectrophotometric measurements of objective-prism spectra

Symposium - International Astronomical Union ◽

10.1017/s007418090005333x ◽

1966 ◽

Vol 24 ◽

pp. 118-119

Author(s):

Th. Schmidt-Kaler

Keyword(s):

Progress Report ◽

Two Dimensional ◽

Objective Prism ◽

Made In

I should like to give you a very condensed progress report on some spectrophotometric measurements of objective-prism spectra made in collaboration with H. Leicher at Bonn. The procedure used is almost completely automatic. The measurements are made with the help of a semi-automatic fully digitized registering microphotometer constructed by Hög-Hamburg. The reductions are carried out with the aid of a number of interconnected programmes written for the computer IBM 7090, beginning with the output of the photometer in the form of punched cards and ending with the printing-out of the final two-dimensional classifications.

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Progress report on 21-cm observations at low latitude between longitudes (l 11) 0° and 66°

Symposium - International Astronomical Union ◽

10.1017/s0074180900100907 ◽

1967 ◽

Vol 31 ◽

pp. 177-179

Author(s):

W. W. Shane

Keyword(s):

Preliminary Report ◽

Progress Report ◽

Galactic Centre ◽

Low Latitude ◽

The Third ◽

Introductory Lecture ◽

Centre Region

In the course of several 21-cm observing programmes being carried out by the Leiden Observatory with the 25-meter telescope at Dwingeloo, a fairly complete, though inhomogeneous, survey of the regionl11= 0° to 66° at low galactic latitudes is becoming available. The essential data on this survey are presented in Table 1. Oort (1967) has given a preliminary report on the first and third investigations. The third is discussed briefly by Kerr in his introductory lecture on the galactic centre region (Paper 42). Burton (1966) has published provisional results of the fifth investigation, and I have discussed the sixth in Paper 19. All of the observations listed in the table have been completed, but we plan to extend investigation 3 to a much finer grid of positions.

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