Mechanical properties of low alloy steel sintered at conventional and high temperatures.

intermediate detected

phases, after

6OOoC.

A15Fe2

heat

Fe3Al-XC

8OOoC.

Powders

formed

Fe3AI-TiC

and A13Ti

treatment formed

milled

after

or

heating

for over

200

at

hours

The demand need

for net shape

to control

cussed.

directly.

Dimensional

additions

change

changes

were dis-

in samples

Fe powder

and sintered

made

with small alloy

in N-H were investigat-

ed. The results were analysed

statistically.

PM~TEC~OOI. The Abstracts which fol2001

Effect of alloying method on dimensional changes during sintering of bearing caps

Metallurgy and Particulate Materials,

Dimensional caps

were

method

that the need for delubrication

F’M parts slows processing

down. current

mg of how lubricant increases

of

Development

and

latest

in delubrication

use of

data

of delubrication

showing

sintered

which

Acrdwdx,

without

Mechanisms

and

with

during

reference

bums

with reference results

ments

of

investigated

of moisture.

C02,

to the

out at 6OOoC to

metallic

kinetics

bons were detected

NH3

apphcations.

The effects of adding

Delubrication

The results

The results

with

ty, prior

particle

increased

%B

borides

up to 2OOoC parame-

and structure.

to lead

with enhanced

to improve-

PM parts.

porosi-

elongation. thin

which

With plates

at

influenced

the

Powder injection moulding A microstructural model for feedstock homogeneity

much

et al. (Pennsylvania between

State LJn~uerslty,

feedstock

were discussed.

is still unknown

between tions

feedstock

and

part

ditions

and that

about

properties.

as functions

acteristics.

quality

It was noted

the relationships

characteristics,

model was used to predict

and

microstructural

optimum

of powder

properties

process condi-

A

Effects of feedstock

rheological

mixing

con-

and binder

char-

homogeneity

on

and debinding

behaviour

a link between

feedstock

and part quality

It was reported of injection It was noted steel powder ability

and

that

is competitive

with some other often

prealloyed

0.85wt%Mo

has good compressibility,

used

in cost

prealloyed

in

at

energy

notably

at higher

12600C

2%Ni.

was demonstrated.

analysis

of

gas to Nand meawithout

the

It was

shown

that

delubrication

the endogas.

as a

com-

properties with

sintering

influence dynamic

steels,

conventionally

and sintered

Effects of composition of pure iron on dimensional change in sintered parts

of sintering

and

above

at higher

Effects 112OoC,

of

temperature

properties and

ing, packing functions

temperatures, sintering

on dimensional

developed.

behaviour at the

of feedstock

mould

of the injection

and

cooling

wall

into

stages,

were carried

fillout as

of temperature.

Analysis injection

of sintering moulding

stage in powder

Korea.)

D.Yoon et al. (Bestner Inc.,

sintering

of injection

parts had been simulated

numerically.

Shrinkage,

that

distortion

and

investigated

experimentally

Temperature

and density

sidered.

of

compacted, was inves-

tempcraturcs, changes

simulation

been

It was shown

grain

growth

were

and by modelling. gradients

that

were

con-

the modelling

was

by the experiments.

on

of a range

warm

had

rheological Analysis

validated

tigated.

Dimensional change

took

moulded

Effect of sintering temperature on properties of low-alloy high-strength steels The

a numerical

slip phenomena

It was reported

densities.

static

that

moulding

high

effect was found

of high-temperature

and

account.

It is

and were

to mechanical

The greatest

impact

with

at 112OoC

sintering

with reference

compared

steel powders.

conjunction

sintering

This

harden-

Imc.,

and

January 2002

up to 0.8%8.

USA.)

of Fe base

and material

shown

was

sintered

properties.

parts quality

expansion

measured

phase

formed

boundaries

shape

to reduce

size and

Integrated numerical injection moulding

and density.

Fe parts were inves-

were calculated

compared.

dew points

result of adding

endothermic

in sintering

Dew points

MPR

were described.

and

and hydrocar-

J.R.Forster et al. (Alleyheny Powder Metalltrra, USA.)

40

Cu or diffusion

in properties

were

temperature

were

Fe powders

in %B was reported

Mechanical properties of low alloy steel sintered at conventional and high temperatures.

pared

endogas

from

homogeneity

Improvement in delubrication by addition of endothermic gas nitrogen-hydrogen atmosphere

higher

liquid

High-performance steels

Conventional

sured.

the

of

in presence

in the effluent.

for special

H atmospheres

on samples’

Relationships

to process

in processing

were discussed.

tigated.

investigated coarse

of boride

particle

residues. removal

of the study were used in development of sensors for use during sintering and in design of lubricants

were

ters and variations

of during PM parts of total removal of

leaving

were

absence

to

particularly

of PM ferrous

of thermal

alloys

of boride

of

to properties

of %B and morphology

Effects

were examined

were discussed

Acrawax

elements,

variations

sintering

with reference

of bearing

regard

as elemental

Statistical

Coefficients

of a

rates were reviewed.

The need for lubrication making and the importance

66OoC

alloy

Thermal expansion materials

The

Mechanism sintering

lubricant

with

G. .S~luaet al. (M&n Polytechnic, Italy.)

understand-

flows from the interior

surface

particles.

R.M.German

of delubrication to the

of adding

bonded.

m sintering

practices

H.S.Nayer. (TAT Technologies inc., USA.)

part

changes

investigated

Cu. Cu was added

Delu brication

practices,

as a function

mechanical

May.

of B in enhancing

prior particle

which was held in New Orleans, USA, in

It was noted

effect

steel was discussed

Increase

International Conference on Powder

Delubrication

The

PM parts and the

dimenslonal

from water atomised

low are of papers presented at the

et itl. (Pcnnr~lvcmra State University,

R.M.G~rmun USA.)

were

at 4OOoC

were

described.

Injection powder

of titanium

L.E.LaVule. (Titanium Products Inc., USA.) Use of TI materials was

reviewed.

moulding ficulties

Precipitation of borides and effect on properties of sintered iron alloys

moulding

and parts in engineermg

Researches

into

of Ti were reported. and requirements

tion of Ti powders

injection

Experiences,

for successful

were described.

difinjec-

Examples

parts were presented.

www.metal-powder.net

of