nitriding
and sintering.
composite
Wear properties
were shown
to be superior
posites made from premixed anodised
Al alloys. The
under oil lubrication
of the to com-
powders and hard-
coefficient
Characterisation of hardmetals by a scanning depth hardness test
of friction B.Roehuck Teddington,
was said to be exception-
et
al.
non-standard
It was noted limited that
that
PM use of Ti was more
development
was likely to change atomisation
UK.)
metals
of new this. These
techniques
and
technologies included
new
for high quality
pow-
ders and mechanical
alloying
at low levels
contamination.
powders
can be consoli-
dated
The
by conventional
means
extrusion
and injection
methods
including
direct
laser
moulding
and
as HIP,
or by new
hardness,
was described.
variation
test machine,
using depthThe
was were
WC-
coated
material
to evaluate
device
to map
hardness
WC Data
hardness
maps
carried
out on a
the ability variations
into
shapes.
in
progress
work
These were
reviewed.
of the through
Three-dimensional
bimodal
WC-Co
tribution
in
scanning
electron
sections
and
algorithm.
were nitrided
by PM
Samples
cut from
in two stages
to 1500°C.
The second
in the
stage was
to allow TiN precipitates
to grow. Ductile/brit-
tle transitions
-200°C
between
temperature,
microstructure
and ambient
and bend strength
were investigated.
It was shown that the nitrid-
ing was effective
in improving
embrittlement
characteristics.
was
It was noted 0.3%La201
analysed
Measured
population
tions
considered.
to
a
bimodal
by
automatic fitted
prisms
and bimodal The
range
of
character
by
materials
an was
of trigonal
Unimodal
were
investigated
data
to
a
of condistribu-
method
WC-Co of the
the
size dis-
of
Keutte,ALcstria.)
C.Stallybrass et al. (Plansee AC,
grain
microscopy
stant shape.
The
were prepared
and rolled to sheet.
Effects of atmosphere dew point ‘on sintering doped molybdenum
A.Lackner et nl. (Plansee Tizit AG, Reutte, ALcstria.)
applied
University, Okayama, Japan.)
alloys
into the substrate.
Analysis of bimodal grain size distribution in tungsten carbide-cobalt
model
methods
range 800°C
described.
with
Tests
Mo-0.5wt%Ti the sheet
machine
with unconventional
uniformity
obtained.
the coating
auto-
A study of conventional
size distribution
concerning
of a new
Mechanical properties of nitrided molybdenum-titanium alloys M.Nagae et al. (Okayama
in mechani-
was reported.
Co and a material
were
have
that need char-
computer-controlled
deposition
techniques
such
of
high-speed
sensing
Laboratory,
hardmetals
Development
mated
grain
newer
for spatial
cal properties.
than for other non-ferrous
the
that
Physical
microstructures
acterisation
Recent developments in PM of titanium (DERA Farnboro~~h,Hampshire,
(Natwnal
UK.) It was noted
ally low.
P.S.Goodwin.
High-performance PM materials
was
grades.
distribution
that
during
atmosphere
entrapped
increased.
in the core
ing a dew point
gradient.
atmosphere
and structural increased
that the
densification.
of dew point
were
described. dew
temperature
dry H was higher
is creat-
on densification
increased
Density
of
Moisture
Effects
evolution
shown
moist
of MO-
of the samples,
of the sintering was
sintering
in H the water vapour content
onset
of
of samples
sintered
in
in samples
sintered
in
than
for
It
point
H.
was discussed.
Sliding wear of cemented carbides
Hard materials Novel plasticiser for extrusion cemented carbides J.C.Zhou, B.Y.Hwng. (Central Technology, Changsha, China.) It was reported extrusion
that
processing
materials
had been
of
structures
up to 25mm cessing
Wear
plasticiser
cemented
developed
for
and that use of
and good properties Properties
including
of
carbide
of materials
in diameter.
stages,
B.LJhreniu, et al. (AB Sandvik Hardmaterink, Stockholm, Sweden.)
of
South University
a novel
this had led to production uniform
thermal
with in rods
and pro-
tigated. Parameters of Cr3CZ,
Tic
increased
in various materials
MPR
Austria.) media
and
was inves-
and effects of additions
and TaC. by
the
Corrosion refractory
in abrasion
tests
inversely
dependent
on
considered
wear
October
rate
hardness.
difficult
to
Sliding
wear
predict
Fragmenting
from was
wear
phenomenon
mechanisms wear
being
Sliding
to be a surface
resistance carbide
2002
P.Polcik etal. (Plansee AG, Creep
50MPa,
1100°C
lower than
and
exponent
bulk
properties.
were
elucidated.
for
be
and
10
often
to
encountered,
A Norton-type were calculated
self-diffusion
mechanism
effective
that cemented
produced ment.
The
without
is shown
toughness
1.5 times greater
cemented
carbide
resistance.
Large
and
equip-
to have fracture
shown
to
could
main
dislocation
of the alloy elements were compared
for
Sintering of an MoFeB cermet and its composite with SIC fibres D.Rao, G..S.LJpadhyaya. Kanpur, India.) A MozFeBz_ composite
based
containing sintering
Vacuum
sintered
be made
Material
with Sic
of the need for high pressure
The be
creep reduction.
by two
higher
Activation
and were lower than
Effects
wear
than conventional
lo-times
components
mate-
had been
use of high-pressure
material
due to avoidance
carbide
particles
much
for up to 500
mechanisms.
was
900°C
creep law, with a stress
used, B, K, Re amd LazOj,
rials with dispersed diamond
both
of 1.0, was identified.
rearrangements.
cemented
of W and W
to
hours.
to
stability
in the ranges
energies
considered
Reutte, Au&a.)
and structural
alloys were investigated
was
important.
in manufacture.
additions.
46
measured
It was reported
studied included WC parti-
cle size, binder content
was discussed.
H.M&gxhi et al. (Swmitomo Electric Industries Ltd., ltami, Japan.)
ofLeoben, L&en,
resistance,
pH, of a range of WC-Co
was
carbide
that wear rate is often
Diamond-dispersed carbide material
Effects of carbide additions on corrosion of cemented carbides Corrosion
of cemented
It was noted
debinding,
were investigated.
G.Mori et al. (University
Creep of tungsten alloys under low stresses at 900°C to llOO°C
mechanical
(Indian cermet Sic
cycles, material
Inst. of Technology, and its layered
ftbres were prepared in
H
or vacuum.
had lower porosity.
fibre had lower density
properties.
Structures
and
and proper-
ties were described.
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