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Mar 01, 1921 |
Solid materials have small/invisible cracks postulated
A.A. Griffith postulates that solid materials contain
small, often
invisible cracks which are extremely efficient levers in
prying atoms
apart.
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Apr 19, 1921 |
Composition of two acid-resisting alloys disclosed
A.W. Clement discloses the composition of two acid-
resisting alloys,
one having 10% molybdenum, 80% cobalt or nickel, and 0.1-
4.0%
manganese, with of without 10% iron, the second lacking
manganese.
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Jun 15, 1921 |
Slip interference theory of hardening proposed
Z. Jeffries and R.S Archer propose slip interference theory
of
hardening.
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Aug 13, 1921 |
Small amounts of boron can harden
R. Walter is apparantly the first to recognize that only a
very small
percentage of boron is required to produce an appreciable
hardening
effect.
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Aug 16, 1921 |
Alloy with specific gravity less than 2.7 described
A. Pacz describes an alloy series from which machinable
castings
having a specific gravity of less than 2.7 can be formed,
consisting
of 8-20% silicon and 92-80% aluminum.
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Oct 19, 1921 |
New transparent adhesive
Formaldehyde condensation products with carbamide or its
derivatives,
prepared by H. John, are described as good, transparent
adhesives,
usable for joining glass, metals, and other materials or as
a laquer
for coating airplane wings or other fabrics.
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Dec 01, 1921 |
Recrystallization diagram of aluminum presented
E. Rassow and L. Velde present a recrystallization diagram
of
aluminum.
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1922 |
Boron is introduced into steel
H.W. Gillet and E.L. Mack combine aluminum and ferroboron
in order to
introduce boron into steel.
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Apr 01, 1922 |
Method for preparing cellulose ethers is patented
L. Lilienfeld patents a method for the preparation of
cellulose ethers
and notes their possible use as adhesives.
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May 30, 1922 |
Salts are catalysts to harden urea-resin adhesives
F. Pollak reports the use of salts of strong acids, i.e.
ammonium
chloride or nitrate, as catalysts to harden urea-resin
adhesives.
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Jun 08, 1922 |
Ethyl derivatives of cellulose prepared
L. Lilienfeld prepares ethyl derivatives of cellulose
soluble in water
below 16 degreees and insoluble above by treating
derivatives soluble
in water above 16 degrees with caustic alkali.
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Jul 01, 1922 |
Variation of diffusion coefficient result of activation process
S. Dushman and I. Langmuir, General Electric, show that the
variation
of the diffusion coefficient in alloy systems is the result
of an
activation process.
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Aug 01, 1922 |
Structure of different types of iron demonstrated
A. Westgren and G. Phragmen demonstrate that alpha, beta,
and delta
iron are all body-centered cubic, while gamma iron is face-
centered
cubic, and that solid-solution austenite is an interstitial
solid
solution.
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Sep 05, 1922 |
Beryllium metal produced
A. Stock and H. Goldschmidt produce beryllium metal by
electrolysis of
fused bath sodium and beryllium fluorides.
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Sep 20, 1922 |
Condensation product from formaldehyde and urea
H. Goldschmidt and O. Neuss produce a condensation product
from
formaldehyde and urea in the presence of acids and acid
salts.
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Oct 25, 1922 |
Coating for airplane wings of cellulose acetate formed
H. Gault develops a coating, formed of cellulose acetate in
combination with other compounds, to be used on airplane
wings covered with cloth fabrics.
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1923 |
Alloys studied by X-ray diffraction
While studying alloys, particularly solid solutions, by
means of X-ray diffraction, E.C. Bain discovers
superlattices, demonstrating the maintenance of the solvent-
lattice type in primary solid solutions and the variation
of the lattice spacing with variation in solute
concentrations.
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Feb 13, 1923 |
Vinyl chloride is formed
Vinyl chloride is formed by the reaction of hydrochloric
acid on nascent acetylene in a process developed by H.
Plauson.
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Mar 01, 1923 |
Plastic strain can be resolved into shears along crystal planes
G.I. Taylor and C.F. Elam prove that observed plastic
strains can be resolved into simple shears along crystal
planes marked by slip lines.
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Apr 01, 1923 |
One-piece, solid duralumin propeller test results reported
S. Albert Reed reports results of tests with his one-piece,
solid duralumin propeller.
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