GENERAL DESCRIPTION

FORMING AND SHAPING PROCESSES
COMPACTION AND SINTERING (PULVERPRESNING)

©Institut for Procesteknik
Danmarks Tekniske Universitet 1996

Powder compaction is used to shape ceramic and metal parts from powder materials. For several materials like ceramics and metal-ceramic blends (usually powders), this is the most used and common technology for shaping them.

PulverpresningThe technology involves the following steps:
a) The starting powder is prepared.
b) The powder is formed into a desired shape (green body), which can be furtherly worked.
c) The green body is sintered at a high temperature (densification). Frequently a combination of high-temperature and pressure (hot pressing) is used.
d) The sintered compact is finished into the final shape.

Sintering is a common technique for consolidating powders. It is essentially a removal of the pores between the starting particles (accompanied by shrinkage of the component), combined with growth and strong bonding between particles.

The process is carried out by heating up the "green" part at about 80% of the melting temperature, until full strength is obtained (10 min. to several houres). The biggest problem of this technique is the shrinkage which causes cracking, distortion, etc.

There are many methods for sintering a component. The most important are: vapor-phase sintering; solid-state sintering; liquid-phase sintering; reactive liquid sintering. Overpressure sintering uses also pressure to accelerate the densification.

ECONOMY

Der er regnet med processerne: Blande, presse, sintre og vibrationsafgratning for alle emnerne.

Der er regnet med to materialetyper:

Jern = ulegeret jern (NC 100.24) med vægtfylde 6,5 (Sint-C00, DIN 30.910)
Stål "Distaby AB" + 0,6% C med vægtfylde 7,0 (Sint-D39, DIN 30.910)Priser i DKK pr. stk. ved leverancer på 1.000 - 100.000 stk.

1.0002.0005.00010.00020.00050.000100.000Værktøjspris
Knast 5 mm, jern4,882,771,51,080,870,740,7023.000
stål5,032,911,651,221,010,880,84
Knast 30 mm, jern6,764,653,382,962,752,622,58
stål7,635,524,253,833,623,493,45
Skiver, jern20,6412,988,386,846,085,625,4731.000
stål22,0414,389,788,247.487,026,87
Dyse, jern8,055,053,252,652,352,172,1146.000
stål8,775,773,973,373,072,892,83

Priser i henhold til Dansk Sintermetal. De valgte emner anses ikke for repræsentative for de fire klasser (produktionssværhedsgrader).

RELEVANT PRODUCERS

  Dansk Sintermetal A/S

This page was last updated on 29.07.1996, Torben Lenau, Thomas Nissen, DTU.