Copper
yield stress and critical
Studies of copper-based memory alloys
shape
Shape were
memory
properties
investigated
improving mates.
of Cu-based
with
the
performance
some with additions
to
of
in cold
3.5)Ni
cli.
alloys,
of Ti, B and C, were stud-
ied. Ti, B and C increased alloy and lowered
alloys
objective
for use
Cu-13.9%Al-(3.2
and increased
alloys showed
reduced
critical
Y.Suzuki et al. (Hokkaido National Industrial Research inst., Sapporo, Japan.) J.Japan Sot. Powder/Powder Met&., Vol47, No 8, 2000, 830s837..lapnnere.
the strength
the shape memory
of the
transition
Initial stages of sintreing
of nano-crystalline were
Fe,
Fe powder
steady
state,
reached.
during
investigated.
coarse
With
refinement
further
an
is gradual
milling
and a
grain
is
boumdary
relaxation was detected. It was deduced that nano-crystalline materials, with the same grain size may exhibit on
the
differing
properties
microstructure
metastable
of
the
depending numerous
in real powder
and properties
from
that steel foams had been pro-
Fe-2.5%C
MgC03
or
Densities
were
were carried Heat
tion,
changing and
as the
38 to 64%.
with
0.2wt%
foaming
agent.
Mechanical
out to determine
tion ferrite
powder
SrC03
treatment
energy
resulted
the range
absorp-
that
of particle
from
the ductile
pea&e
to
response
to
agglomerated ment
alloy powder
made by heat treat-
and from pulverized
alloy powder.
The
the best performance.
Preparation and use of magnetic fluids S.L.Liu et al. (Central Iron d Steel Research Insr., Beijing, China.) PM Industry, Vol IO, No 5, 2000, 3239. In Chinese. Methods
of making
metal
oxide,
Fe4N
powders
described. bearings,
metal
magnetic
and
and
operating
Applicadons grinding
fluids,
compounds
from
such
principles
as
were
of such fluids in seals,
and damping
were discussed.
Hard materials and tool steels
M.Rosso et al. (P&technic ofTorino, Torino, It&.) ht. J. Refracr.Met&/Hard Mnter.,Vol 19, No I, 2001, 45 52. to improve
of parts was discussed coating.
Studies
thermally
stainless
with reference
rosion
resistance
The coatings
coatings
3 or on 416
with a Ni-Cr
The coatings
bond
SLuyckx et al. (University of Witwatersrand, Johannesburg, South Africa.) int. J. Refracr.MetnIs/Hard Mater.,Voi 19, No I, 2001, 41-44. Investigations of the effects of up to 3wt%Ru added to WClO%Co are described. It is shown that
the hardness
reduced inhibitor
of WC
abrasion
resistance
binder
is increased
and
as the %Ru is increased.
high cor-
and acid solutions.
were characterised
Effect of ruthenium on hardness, toughness and grain size of tungsten carbide-cobalt
are shown
and to confer
in saline
to
the effectiveness
sprayed
to have good adhesion
resis-
of A1203-(0,
steel pump pistons,
layer, were described.
corrosion
grain
growth
due
toughness
Ru is a weak and
improves
to hardening
of the
phase.
by microhard-
ness and microscopy.
Sintering features of tungsten carbide-cobalt processed from fine powders
in decarburiza-
the structure
increasing
tests
were
Corrosion resistance and properties of pump pistons coated with hard materials
13)TiO2
duced
systems
of 3 Ag-I’d
Coatings
of the
288, No 1, 2000, 111-118.
data
It is emphasized
the effect of pores in reducing
of
S.R.Nutt, C.R.Pnrk. Mater Science/Engineering A, Vol
It is reported
the degree of densi-
sizes must be considered.
tance
PM synthesis steel foams
this is
that as the proportion
with a model.
properties
and
in situ
to correct
and electrical
last of these showed
is shown
Experimental
Use of coatings
grain boundaries.
Physical
of large
radiance
increased
pastes from powders
pastes, for use as electrodes in multilayer ceramic devices, were investigated. The pastes were made from co-precipitated powder,
compacts
using
errors and means
decreased.
compared
size range,
proportions
It is reported
of large particles
initial
Silver-palladium
of A1203
Sample
Electrical and magnetic materials K.Koumoto et al. (Nagoya University, Nagoya, Japan.) IJapan Sot. Powder/Powder Metall., Vol 47, No 8, 2000, 844-852 In English.
was investigated
dilatometry.
fication
mechanical
in the nm particle
On
different
particles
to introduce
Y.H.Zhao et al. (Chinese Academy ofSciences, Shenynng, China.) Acta Mater., Vol49, No 2, 2001, 365-375. Structural evolution and thermal properties
and lower
up to 50Cppm.
R.A..Dorey et al. (University @‘Surrey. Guildford, UK.) Acta Mater., VoI 49, No 3, 2001, 519-527.
described.
Structural evolution and thermal properties of iron during mechanical attrition
yield strength
at
Mo-Pd
In situ dilatometric measurements of initial stages of sintering of alumina
optical
Iron and steel
decreased
at 830ppm.
Ceramic materials
small
alloying
temperature
containing
temperature.
temperature
up to 6lCppm
Composite materials
spite of larger pores in the steel.
Multistage sintering for preparation of nickel aluminide-alumina composites
C.H.Allibert. (CRNS-INPG-UJF, St-Martin d’Heres, France.) ht. j. Refracr.MetalslHnrd Mater..VoI 19, No I, 2001,53-61. Use of increasingly fine powders to make WC-Co
Molybdenum
W.C.Chiou, C.T.Hu. (National Tstng Hua Unierersity, Hsinchu, Taiwan.) Metall. Mater. Trans A, Vol 32, No 2,2001,407-415.
between
compressive ty between
loading.
There
was some similari-
the ferritic foams and those of Al in
Low-temperature fracture of molybdenum with small additions nickel or palladium
Production
of
N.Yosizawa et al. (Okayama University of Science, Ok~~yama,Japan.) J.Japan Sot. Powder/Powder Metall., Vol47, No 8, 2000, 824-829. In Japanese. Low temperature with additions investigated. the grain with
fracture
properties
of up 9GOat.ppm It is reported
size and that
increased
alloy
of MO,
Ni or I’d, were
content.
www.metal-powder.net
with
elemental
powders
of
Ni-24at%Al-O.l%B
5 or
lOvol%A1203,
and
B is described. compacted, further
heated deformed
transient formed
The
liquid
phase
and provides
coated
powder
to to
A1203 a low
with
is canned, temperature,
eliminate
pores
sintered.
the liquid
from
phase.
of 14.6 and 8.9%
attained
10%
with
respectively.
Ni alloys
5 and
A1203
and
differences
in
densification
microstructural
mm and nm size particles
evolution are noted.
In the case on nm size powders the large contribution to solid state densification and abnormal grain growth are considered. Factors related to hindrance of densification and grain growth inhibition are identified.
is
Mechanical alloying
In ten-
sile tests elongations for
and
and
Ni2A13
stress decreased
that Ni and I’d refined critical
composites
behaviour
were
materials
Effect of ball-charge fraction on mechanical alloying in vibratory ball mill
MPR
January 2002
37