Effect of process parameters on magnetic properties of praseodymium-iron-copper-boron

with respect to relationship with mechanical processes. It was noted that each material has characteristic

SHOCK-REACTIVE SYNTHESIS TITANIUM ALUMINIDE INTERMETALLIC MATERIALS

mechanical alloying studies of MA powders

T. Katoh et al (University

behaviour. X-ray were described.

FORMATION OF NICKEL-ALUMINIUM INTERMETALLICS BY MECHANICAL ALLOYING R. Orban, S. Domsa

(Technical

University of

Cluj-Napoca, Cluj-Napoca, Romania). Application of MA to Ni aluminides

was

discussed. It was reported that aluminides were synthesized from elemental powders by energetic milling and that nanocrystalline

powders

suggested for

the

were

formed.

that the powders production

ductile-brittle

of

alloys

transition

higher fracture

It was

had potential with

lower

temperatures

and

toughness.

htermetallic

of Tokyo, Tokyo,

produces pressures

H, as a means of producing anistropic permanent magnets, was investigated.

process

transient bursts and temperatures. variables,

detonation

initial

velocity

Microstructures EFFECTS

OF SMALL ADDITIONS

TITANIUM

F. Uberti et al (CISE SpA, Milano, Italy). Effects of small additions, 0.2wt%, of on the properties

Magnetic materials

al

(University

of

Dayton,

The

production

aluminide pressure was

in

of

a fine-grained

Ti-48at%Al-2%Nb

HIP from

reported.

by

gas atomized

The

fl

microstructure

MAGNETIC

and

E.

Schubert

HIP SINTERING

Inst for Dresden,

The development 2%Cr

and

of a TiAl base 2%Nb

was

alloy

described.

Powders were consolidated by CIP and hot extrusion at 350 and 43O”C, at which intermetallics 1250°C

do

not

form.

the microstructure

After

HIP at

was two-phase,

m and cczTi&l. Heat treatment gives a lamellar structure. Structure and properties were discussed. MANUFACTURE ALUMINIUM PARTS

process

industry

was

were

process,

cryogenic

was described. This rates and has been fine spherical

OF TITANIUMELEMENTAL

AGAINST

AND

POWDERS

M. Dahms,

et al (GKSS

Research

Centre,

Germany).

Applications

of

Ti

aluminides

were

discussed. The production of Ti-48at%Al and Ti-48%&2%Cr2%Nb, in sheet, foil and three

dimensional

and prealloyed Structure and and discussed.

parts

powders properties

from

elemental

was described. were outlined

to

ELEMENT

OF NEODYMIUM-IRON-

of Birmingham,

UK)

It was reported

magnetic

properties.

properties were exposed to air.

that powders

Optimum

obtained

magnetic

from

et al (Sintermetal Spain).

It was reported analysis had been

that used

main

bearing

Assembly

are

of

considered

conformity

and

of the

the

mating

The model is shown

to facilitate early stages in the development of the part regarding performance and economy. SINGLE

SINTERED

CONNECTING

RODS FOR PASSENGER ILLUSION?

CARS

-

AN

et al

The

single

cover

(Fraunhofer

Darmstadt, sintering

of about

Inst. fir

Germany).

technique

‘I.lgm.cm-a

the requirements

with

is said

of engines

to

in the

range 1.5 to 2.0 and running up to 7000 rpm and offers, if fracture splitting

I.R. Harris et al (University

of Birmingham,

UK).

It was reported been

cap.

arising when the part is fitted to

crankcase

densities

OF

BORON

had

finite element to determine

powders

EFFECTOFPROCESSPARAMETERS

Birmingham,

SA, Ripollet,

stresses, tolerances and to define manufacturing operations for a sintered

C.M. Sonsino

ON MAGNETIC PROPERTIES PRASEODYMIUM-IRON-COPPER-

OF A

MAIN

Barcelona,

importance

The use of H decrepitation in the processing of NdFeB magnets from powder was discussed.

wear

CAP

surfaces is emphasised. Birmingham,

of

Engine

good

ANALYSIS

A. Romero

the

POWDERS

I.R. Harris et al (University

show

AUTOMOTIVE

Betriebfestigkeit, Geestacht,

were outlined.

reported

BEARING

stresses,

partially degassed after H decrepitation showed improved oxidation resistance and

BASE MATERIALS

FROM

OXIDATION

respect

a small

powders with a narrow range of particle sizes. Magnetic properties were reported.

BORON

in

Vileck,

and the need to attain

STABILITY

weight

automotive

in the alloy.

FINITE

IMPROVED

the

discussed

the fitting technique tests

(WZEVUS,

novel

in

camshafts. The complete valve train is said to be extremely complex and the use

SINTERED

A

costs

automotive

Germany) with

OF

HARD

used with NdFeB to produce B. Kieback et al (Fraunhofer Applied Materials Research,

and

Production of NdFeB magnetic powder materials was discussed with reference to size.

Sintermetalltechnik

GmbH, Giessen, Germany). The need to reduce component

behaviour

al

liquid gas atomization gives high quenching

ALUMINIDE

H. Cohrt et al (Schunk

Germany)

domain

OF

et

CAMSHAFT

steel met the requirements of the camshaft. The principles of material development and

POWDERS

properties EXTRUDED TITANIUM BASE MATERIALS

AND PROPERTIES

GAS ATOMIZED

AND

FOR AN

of assembled camshafts was considered. It was shown that a low cost sintered MO-C

high

powders

properties were described and are said to be superior to cast/wrought materials. REACTIVE

internal

were described.

PRODUCTION LIQUID

OF MATERIALS

TECHNIQUE

AUTOMOTIVE

ALUMINIDE

ALUMINIDE et

ASSEMBLY

OF

oxidation and influences properties. Effects on structure and properties, including

Dayton, Ohio, USA).

from the tetragonal c-axis plane during adsorption of

DEVELOPMENT

OF

ON PROPERTIES

of easy

Structural applications

were outlined.

RARE EARTHS

magnetization to easy basal

The possibility direction of

and

investigated.

corrosion,

Eylon

of high Effects of

porosity

were

FORGING ROLLING AND NET-SHAPE PROCESSING OF TITANIUM

D.

were superior to as cast Effects of H adsorption

were considered. changing the

of T&Al were studied. RE promotes

BASE MATERIALS

magnets materials.

Japan). The use of large scale shock waves to synthesize Ti aluminide from elemental powders was described. The technique

rare earths, mischmetall,

materials

powder and PM technology. Effects of heat treatment on magnetic properties were described. The H decrepitated

FOR

made

that Pr-Fe-C&B by

magnets

H decrepitation

of

is used

on the big-end

reliable

means

weight

scatter

dimensional

of of

an economic

manufacture f5gm

and

and

with good

accuracy.

MPR February 1995 43

a