Powder metallurgy

Using water as a suspension medium, instead of organic solvents, for the preparation of hard metal powders has ecologic advantages and, as a general rule, helps to cut costs. The application of an oxidation inhibitor is recommended to reduce oxygen absorption of hard metal.

• INHIBITORS Overview

Pressing agents and lubricants improve compaction of powder metallurgical granules during the pressing process. This leads to an increase in density and a reduction of microstructural tensions. Internal friction of the body, and/or between the pressed article and the mould wall is reduced. Furthermore, optimal separation of the pressed article from the pressing tool is obtained.

• PRESSING AGENTS AND LUBRICANTS Overview

Stabilisers can be used to produce metal powder suspensions that are not prone to sedimentation and which remain stable during prolonged storage times.

• STABILISERS Overview

After the shaping process, it is necessary for the powder metallurgical components to have sufficient strength to withstand further handling during subsequent processing steps. The use of temporary binders allows an increase in green strength and modulus of rupture, as well as an improvement of edge strength.

• TEMPORARY BINDERS Overview

Lubricants reduce the internal friction of the extrusion body and the friction between the body and the extruder screw and die.

• LUBRICANTS Overview

Using water as a suspension medium, instead of organic solvents, for the preparation of hard metal powders has ecologic advantages and, as a general rule, helps to cut costs. The application of an oxidation inhibitor is recommended to reduce oxygen absorption of hard metal.

• INHIBITORS Overview

The addition of wetting agents promotes reduction of surface tension of the preparation water. The use of wetting agents further makes it possible to incorporate compounds that are normally difficult to wet more readily. Last but not least, wetting agents perfectly facilitate the crushing of all components used during wet grinding.

• WETTING AGENTS Overview

Plasticisers, acting as swelling agents, increase the plasticity of a body. These additives absorb a portion of the available preparation water and increase the workability of the body, thanks to their swelling ability. This makes it possible to manufacture extrusion bodies based on non-plastic powder metallurgical raw materials. On account of extrusion body surfaces being dull in many cases, it is recommended to combine plasticisers with pressing agents and lubricants.

• PLASTICISERS Overview

An interaction of hard metal components with the sintering substrate must be avoided. For this purpose, separating layers are used, for example by applying a suspension based on aluminium, zirconium or yttrium oxide and/or graphite. This prevents undesirable reactions with the sintering substrate.

• RELEASE AGENTS Overview