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High temperature behaviour of oxide dispersion strengthened PM copper alloys
PM’94 The abstracts
which
was
held
Technology,
which follow are of
papers which were presented
in Paris from
Prague, Czech republic)
Bearing materials,
at the 1994
than
6th to
under
hydrodynamic
conditions
were categorised
The use discussed
of
Dispersion strengthened metals and alloys
performance.
HIGH TEMPERATURE
PARTS
PM with
STEEL
discussed
and
ODS
it was A
Cu
tensile
increase
possible
in
explanation,
deduced
from
was suggested.
turing Science,
AND FAILURE
(Inst.
Erlangen,
powder
mixture
(Inst.
for
for failure
fraction
presented.
relationships
and to require low ejection spite
in
during
of
of an skeleton with
of hard phase during
and
loading
St.ructure.‘property
were
was
processing
emergency
running of
STRENGTHENED
MATERIALS J. Lccomte-Beckers
et
al
to
shown
which
of
lubricants. to
resulted
in good
properties.
non-metallic
The
surface
layers
(liniversity
OF DAMAGE
WEAR OF NITRIDED STEELS 0. Molinari
et
al
of
Trento,
Trento, It.aly) responsible
for
surface
of
discussed
and
properties.
related
to
structure
Conditions
under
oxidative
wear, diffusion
cracking outlined.
of
MAKING
OF COMPOSITE
white
and which
wear and brittle
nitrided
layer
were
improved
mechanical
oxidation using
resist.ance
mechanical
The attainment service
of ODS Fe alloys with
up
to
optimization
ALUMINIDES
and
at high temperatures, alloying
was
of properties 1200’ C was
of composition
conditions. Evolution was discussed. SYNTHESIS
properties
reported.
suitable
for
attributed
to
and
of textures
process in tubes
OF TITANIUM POWDERS
O.M. Ivasishin et al (Inst. for Metal Physics, Kiev, IJkrainc) Synthesis of TiAl and Tit3Al from TiH2 and Al powders was described. IJse of TiH, instead of Ti powder was reported to give more rapid synthesis of the aluminides. The sequence
of phase transitions
Improvements
in ductility
was outlined.
were reported.
Tribology and Materials ROLE OF POWDER METALLURGY SELF LUBRICATING BEARING
IN
MATERIALS \‘. Dufek
(Society
for New Mat,erials
K.K. Shugay
et al
Manufacture described. sintered
(Don
Rostow-on of
Various on
Densities adhesion
to
plain
Technical
bearing
thin powder
sintered
of the between
State
Don, Russia)
steel
thin layers layer and
was
layers were substrates. and the substrate
and
of
in
(Chalmers
IN
Ilniver-
Geborg, Sweden.) of the effect of particle of
metal
powder
was
use being made of measurement
of pressure
gradients
a tube
over a bed of powder
during
evacuation.
Effect
of
size on gas flow conductance
was
Pressure within the powder t,o be greater
depend on condition. CONTROL
particlo
for small size
S.V. Bogun
et al
to
surface
OF WATER
METAL
POWDERS
(Zaporozhye
versity, Zoporozhye,
bed
particle
is shown and
OF PROPERTIES
AND GAS ATOMIZED
State
lini-
IJkrainc)
1mprnvrment.s in atomization processes, giving better powders, were described for pilot plant scale operations. atomization
models
BEARINGS
IJniversiQ,
giving basic
phenomena.
1,. Nyborg
degassing
were
prediction
were determined. It was reported that improvements in layer/ substrate adhesion
FROM TITANIUM
HYDRIDE AND ALUMINIUM
on
described
of PWN
of
of magnitude
sizes. The limit for degassing
SINTERED
(I:niversity
experiment
An investigation size
is shown
DURING
Liege, Liege, f
T. Tunberg,
particle
wear resistance.
boundary
were compared
for t.he order and predicted
on
droplet
ROLE OF GAS FLOW CONDUCTANCE METAL POWDER DEGASSING
be form
is based and
Predictions
sity of Technology,
damage during wear of plasma nitrided and heat. treated PM Fe-Mo alloys were
OF IRON BASE
OXIDE DISPERSION
absence
reported
MnS
Mechanisms
AND
RESCRYSTALLIZATION
the
compaction
model
growth
at the turbulent
agreement
evaluated.
were discussed.
PROPERTIES
to have high
pressures
EVOLUTION
of the skeleton
The
wave
observed
Superhard
of a hard phase in sintered composites a high volume
Germany)
compressibility
formation
Kiev, IJkraine.)
Models for the formation
for Manufac-
was reported
were shown to enhance
Materials,
of a model for atomization
described.
detachment
The development of a Fe base alloy with graphite and MoS, was described. The
satisfactory.
CONTENT
wore
M.Geige.
of Stuttgart,
Germany)
the metal jet.
Properties
WITH HIGH FILLER
L.L. Mishnacvsky
E. von Berg et al. (Ilniversity Stuttgart,
surface
FOR WEAR LOADED
conventional
microstructural
FOR SINTERING
OF COMPOSITES
were
that
with
observations, MODEL
alloys
noted
decline
temperature.
in manufacture was regard to service
with a simulation
f? Dupeyrat et al (Laboratory of Physical Metallurgy, Poitiers, France.) (In French).
properties
JETS
ALLOYED WITH MOLYBDENUM
F. Vollertsen,
FOR GAS
OF LIQUID METAL
and discussed.
STRENGTHENED
PM COPPER ALLOYS
of
lubrication
ATOMIZATION
Development
DISULPHIDE
Properties
other
was
BEHAVIOUR OF
OXIDE DISPERSION
PROCESS MODELLING
for applications
and discussed
of particle
Hydrodynamics
physico-mechanical with
reference
to
size distribution.
Pressing A FIRST STICK
ORDER
MODEL
PHENOMENA
EJECTION
OF POWDER
A.Bocchini.
KEsposito
pies, Naples, Italy) E,jection curves
OF SLIP-
DURING COMPACTS
(University
were
discussed
and
it
had been attained.
was noted
Powders
study the problem was described. Friction and forces in the die and compact were
practice
NUMERICAL SIMULATION WATER ATOMIZATION B. Sustaric
OF GAS AND
(Inst. of Metals and Tcchnolo-
gies. Ljubiana,
Slovenia.)
Modelling of gas and water atomization, in order to predict particle sizes and shape and cooling rates, was discussed with reference to microstructures of powders. 1Jse of a computer based model, in which process parameters can be varied, was described. Some speed steel and presented.
observations for Co-based alloys
high were
that the ideal is smooth
of Na-
is often serrated.
considered
A model
but in used to
using finite element analysis for
validation. ON-PROCESS
NON-DESTRUCTIVE
EVALUATION
OF COMPACTS
ULTRASONIC
ARRAY SENSING
BY
JKihara
et al (IJniversity
of Tokyo. Tokyo.
.Japan) The
lack
for
of
means
monitoring of compact pressing was noted. A array sensing method was prototype for mechanical
in-process
quality during new ultrasonic proposed and a characterization
MPR March
1995
39
which
was
held
Technology,
which follow are of
papers which were presented
in Paris from
Prague, Czech republic)
Bearing materials,
at the 1994
than
6th to
under
hydrodynamic
conditions
were categorised
The use discussed
of
Dispersion strengthened metals and alloys
performance.
HIGH TEMPERATURE
PARTS
PM with
STEEL
discussed
and
ODS
it was A
Cu
tensile
increase
possible
in
explanation,
deduced
from
was suggested.
turing Science,
AND FAILURE
(Inst.
Erlangen,
powder
mixture
(Inst.
for
for failure
fraction
presented.
relationships
and to require low ejection spite
in
during
of
of an skeleton with
of hard phase during
and
loading
St.ructure.‘property
were
was
processing
emergency
running of
STRENGTHENED
MATERIALS J. Lccomte-Beckers
et
al
to
shown
which
of
lubricants. to
resulted
in good
properties.
non-metallic
The
surface
layers
(liniversity
OF DAMAGE
WEAR OF NITRIDED STEELS 0. Molinari
et
al
of
Trento,
Trento, It.aly) responsible
for
surface
of
discussed
and
properties.
related
to
structure
Conditions
under
oxidative
wear, diffusion
cracking outlined.
of
MAKING
OF COMPOSITE
white
and which
wear and brittle
nitrided
layer
were
improved
mechanical
oxidation using
resist.ance
mechanical
The attainment service
of ODS Fe alloys with
up
to
optimization
ALUMINIDES
and
at high temperatures, alloying
was
of properties 1200’ C was
of composition
conditions. Evolution was discussed. SYNTHESIS
properties
reported.
suitable
for
attributed
to
and
of textures
process in tubes
OF TITANIUM POWDERS
O.M. Ivasishin et al (Inst. for Metal Physics, Kiev, IJkrainc) Synthesis of TiAl and Tit3Al from TiH2 and Al powders was described. IJse of TiH, instead of Ti powder was reported to give more rapid synthesis of the aluminides. The sequence
of phase transitions
Improvements
in ductility
was outlined.
were reported.
Tribology and Materials ROLE OF POWDER METALLURGY SELF LUBRICATING BEARING
IN
MATERIALS \‘. Dufek
(Society
for New Mat,erials
K.K. Shugay
et al
Manufacture described. sintered
(Don
Rostow-on of
Various on
Densities adhesion
to
plain
Technical
bearing
thin powder
sintered
of the between
State
Don, Russia)
steel
thin layers layer and
was
layers were substrates. and the substrate
and
of
in
(Chalmers
IN
Ilniver-
Geborg, Sweden.) of the effect of particle of
metal
powder
was
use being made of measurement
of pressure
gradients
a tube
over a bed of powder
during
evacuation.
Effect
of
size on gas flow conductance
was
Pressure within the powder t,o be greater
depend on condition. CONTROL
particlo
for small size
S.V. Bogun
et al
to
surface
OF WATER
METAL
POWDERS
(Zaporozhye
versity, Zoporozhye,
bed
particle
is shown and
OF PROPERTIES
AND GAS ATOMIZED
State
lini-
IJkrainc)
1mprnvrment.s in atomization processes, giving better powders, were described for pilot plant scale operations. atomization
models
BEARINGS
IJniversiQ,
giving basic
phenomena.
1,. Nyborg
degassing
were
prediction
were determined. It was reported that improvements in layer/ substrate adhesion
FROM TITANIUM
HYDRIDE AND ALUMINIUM
on
described
of PWN
of
of magnitude
sizes. The limit for degassing
SINTERED
(I:niversity
experiment
An investigation size
is shown
DURING
Liege, Liege, f
T. Tunberg,
particle
wear resistance.
boundary
were compared
for t.he order and predicted
on
droplet
ROLE OF GAS FLOW CONDUCTANCE METAL POWDER DEGASSING
be form
is based and
Predictions
sity of Technology,
damage during wear of plasma nitrided and heat. treated PM Fe-Mo alloys were
OF IRON BASE
OXIDE DISPERSION
absence
reported
MnS
Mechanisms
AND
RESCRYSTALLIZATION
the
compaction
model
growth
at the turbulent
agreement
evaluated.
were discussed.
PROPERTIES
to have high
pressures
EVOLUTION
of the skeleton
The
wave
observed
Superhard
of a hard phase in sintered composites a high volume
Germany)
compressibility
formation
Kiev, IJkraine.)
Models for the formation
for Manufac-
was reported
were shown to enhance
Materials,
of a model for atomization
described.
detachment
The development of a Fe base alloy with graphite and MoS, was described. The
satisfactory.
CONTENT
wore
M.Geige.
of Stuttgart,
Germany)
the metal jet.
Properties
WITH HIGH FILLER
L.L. Mishnacvsky
E. von Berg et al. (Ilniversity Stuttgart,
surface
FOR WEAR LOADED
conventional
microstructural
FOR SINTERING
OF COMPOSITES
were
that
with
observations, MODEL
alloys
noted
decline
temperature.
in manufacture was regard to service
with a simulation
f? Dupeyrat et al (Laboratory of Physical Metallurgy, Poitiers, France.) (In French).
properties
JETS
ALLOYED WITH MOLYBDENUM
F. Vollertsen,
FOR GAS
OF LIQUID METAL
and discussed.
STRENGTHENED
PM COPPER ALLOYS
of
lubrication
ATOMIZATION
Development
DISULPHIDE
Properties
other
was
BEHAVIOUR OF
OXIDE DISPERSION
PROCESS MODELLING
for applications
and discussed
of particle
Hydrodynamics
physico-mechanical with
reference
to
size distribution.
Pressing A FIRST STICK
ORDER
MODEL
PHENOMENA
EJECTION
OF POWDER
A.Bocchini.
KEsposito
pies, Naples, Italy) E,jection curves
OF SLIP-
DURING COMPACTS
(University
were
discussed
and
it
had been attained.
was noted
Powders
study the problem was described. Friction and forces in the die and compact were
practice
NUMERICAL SIMULATION WATER ATOMIZATION B. Sustaric
OF GAS AND
(Inst. of Metals and Tcchnolo-
gies. Ljubiana,
Slovenia.)
Modelling of gas and water atomization, in order to predict particle sizes and shape and cooling rates, was discussed with reference to microstructures of powders. 1Jse of a computer based model, in which process parameters can be varied, was described. Some speed steel and presented.
observations for Co-based alloys
high were
that the ideal is smooth
of Na-
is often serrated.
considered
A model
but in used to
using finite element analysis for
validation. ON-PROCESS
NON-DESTRUCTIVE
EVALUATION
OF COMPACTS
ULTRASONIC
ARRAY SENSING
BY
JKihara
et al (IJniversity
of Tokyo. Tokyo.
.Japan) The
lack
for
of
means
monitoring of compact pressing was noted. A array sensing method was prototype for mechanical
in-process
quality during new ultrasonic proposed and a characterization
MPR March
1995
39