Wear transition as a means for evaluation of fracture toughness of hardmetals

It is reported

that

Fe3Al

5, 15 or 25vol%TiB2 been

prepared

by

pulsed discharge during

lOvol%TiC, either, alloying

from elemental

and TiB3were

sintering

pressure

mechanical

sintering

ders. Fe3A1, Tic

with

and without

at 1100°C

process more

and

powder.

in situ applied

in 10 minutes.

HIP and hot pressing of diamond-partially stabilised

zirconia

to make diamond-PSZ

composites

by HIP

and

hot

pressing

conditions

were

unstable

for diamond

but there was no transfor-

to graphite.

of ZrO,

grains

are described.

and

The

thermodynamically

Diamond

inhibited

increased

for

magnetic

field

completely

is

Thermoelectric investigated

properties

with

regard

tions. The material, ment

thermoelectric

attributed

condi-

with excess Na, is sintered, which

ality of the crystallites

This

is

material.

of the

Use of metal

injection

is discussed.

described.

Characterization binder

researches

are

by metal

surface

condition

reagents

on

and

moulding An and

note

99.5%

were attained.

are

of powder

of surface-active

was used to evaluate parameters.

Co

interactions

powder/binder

feedstock

is

and

is taken

and effects

the

to make

investigation of WC

systems

Special

Rheometry

growth

hardness

future

hardmetals

considered.

of two-dimension-

in the sintered

and

A NeJmo et al. Wniuersity oftheAndes, St. Fe de Bogota, Columbia.) Key Engmeer. Mater., Vol 189-191, 2001, 579-585.

powders

gave improve-

properties.

to enhancement

Current

Preparation of tungsten carbide-cobalt hardmetals injection moulding

were

to sintering

and resintered,

on

of NaQO4

described. discussed.

reacted

Microstructure and properties of sodium-cobalt-oxygen thermoelectric materials

reground

process mation

the

than

M.Ohtakr, E.Maeda. (Kyushu Unwersity, Kasuga, Japan.) J.Japan Sot. Powder/PowderMetall., VZ 47, No II, 2000, 1159-1164. InJapanese.

N.Kanatake et al (Nagoya Uniwrsq, Nagoya, Japan.) J.Japan Sac. PowderlPowderMetall., Vol 47, No JO, 2000, 1102-l 106. In Japanese. Attempts

effective

pow-

formed

and 30MPa

is incomplete

had

interface. binder,

mixing

Sintered

densities

Phase changes in water-atomised iron-silicon powders during annealing

above

Electrical and magnetic materials

M, .Hashh et al. (Nagoya Munqml industrial Research Inst., Japan.) J.Japan Sot. Powder/Pou&rMetall., Va1 47, No 11, 2000, 1179-l 183. InJapanese.

Preparation of tungsten carbide-nickel-iron powders by direct carburistion

Gaseous fluorination hydrides

ing to stoichiometric

composite

in comparison

with ZtO,

alone.

It is reported

of metal

by water

M.L. and l.E.Anderson. (Ames Laboratory USA.) .) PM Science/Technol. Briefs, Vol 2, No 3, 2000, 17-20. It is reported had

been

improve

that metal powders,

coated

with

corrosion

life of Ni-metal

a layer

resistance

hydride

tion,

with

rechargeable

gas atomized

in a fluidized

than

5mm

ment

in electrical

of LaF,

and increase

NaF3 was used as the source out

La-Na-Sn,

bed.

powders,

was carried

to gain

size, less

an improve-

performance.

of granulation,

Nd-Fe-B

were

ed powders

were disintegrated

field which

improved

and

magnet-

properties

Magnetic

to those

in a static magnetic

drying,

pulsed

of magnetic

investigated.

ties were superior pacted

by spray

in a high intensity

ic field on orientation

prepared

paction is shown

that from

field. The granulat-

in a magnetic that

at 600°C

to FeSi,

725C.

Xme

to

required

to make FeSi,

powder

for mechanically

trans-

was

alloyed

less than

powders.

that ultrafine

tion of nanoscale were

made

Particle

Hard materials and tool steels

The

objective

of the

was to set limitations in which

wear

resistance

ness of hardmetals and

transitions tions

researches

on a novel

is based

The

and

cutting.

tested

tools with

wear

fracture

of

simulates

condi-

and

during

A range

together

test is

that

by brittle

tribotester

cutting

tough-

The

on findings

are controlled

between

described

test procedure

are combined.

rock

of hardmetals effects

of

pow-

W-Ni-Fe

oxide powders

by an ultrasonic

spray

conditions

sizes were 200nm

that

technique.

were investigated. to 300nm.

Preparation of molybdenum silicide with additions of boron aluminium niobium

of

and fracture

WC-Ni-Fe

by reduction/carburisa-

Intermetallic materials

S.F.Sc&zt. (Unwewty ofSilesia, Gliwm, Poland.) Int. J. Refract. Metals/Hard Mater., Vol 19, No 2, 2001, 101-108.

HIP

H.Harhmoto et al. (Tohoku Natmud Jndusrnal Research Jnst., SOC. Sendai, Japan. ) J .Japan Pow&r/Pow&rMemll., Vu1 47, No 11, 2000, 11501153. In Japanese. It is reported tions

of Al,

mechanical

that

MoSi2

B and

Nb,

alloying

ing. Structures

were

prepared

resulted

MoSiz.

Milling

due to avoidance

except

a better densification

addi-

made

those with Al.

enhancer

by

sinter-

very fine compared

in high density of powders

with

been

and pulsed discharge

conventionally dation

alloys, had

with in Ar of oxiB was

than Al or Nb.

Mechanical alloying Cemented carbides earth additions

by

had

by com-

field and hot pressing.

if the last stage

It is reported

ders had been prepared

processing

magnets

powder

Y.Hongbo et al.(LJnroers~ty of Science and Technology, BeiJing, Chm.) PM Technology, Vol 19, No 3, 2001, 144-147. In Chmese.

Effects of process

were

properties.

Nd-Fe-B

www.metal-powder.net

above atomized

drilling

in the magnetic

magnetic

HDDR

temperatures

pow-

which

on annealing

from

hardmetals.

com-

K.Mmimoto et al. (Mitsubishi Materials Corporation, Omiya, Japan.) J.Japan Sot. PowderlPowderMetall., Vof 47, No 10, 2000, 1085-1090. InJapanese. It is reported

Full transformation

described of

proper-

of magnets

Production of fully dense neodymium-iron-boron magnets hot pressing

been

to bFeS$

725°C.

water

as-atomized

Wear transition as a means for evaluation of fracture toughness hardmetals

Y.Klshmoro, O.Yamashita. (Sumrtomo Specral Metals Co. Ltd., Osaka, SOC. J .Japan Japan. ) Pow&r/PowderMemll.. Vol 47, No 10, 2000, 1067s 1072. In Japanese.

Effects

The

aFezSi5-eFeSi

formed

required

batteries.

Properties of neodymium-iron-boron magnets made from spray-dried powders

compaction

atomization.

comprised

correspond-

FeSi,, had been produced

of F and the reac-

Fine particle

was required

to the

ders

that Fe-Si powder,

in the HDDR

It

containing

rare

C.Xu et al. (Shandong Inst. of Light Industry, Jinan, Chum.1 Jnt. J. Refract. Metals/Hard Mater., Vol 19, No 3, 2001, 159-168. Rare

earth

are reviewed duction

with

properties are

to cemented

consideration

methods

Mechanical mances

additions

summarized

given

and and

carbides to pro-

compositions. cutting and

perfor-

applications

Alloying and amorphisation aluminium-nickel-zirconium planetary mill

of in

R.Tsuzukz, E.Yuasa. (Musashi Inst. of Technology, Tokyo, Japan.) J.Japan Sac. Powder/PowderMeull., Vol 47, No II, 2000, 1144-1149. InJapanese. Elemental cally

Al-Ni-Zr

alloyed

investigate

in

powders

a planetary

phase evolution

MPR

were mechaniball

mill

to

and amorphisation.

March 2002

55