CPL - Chalmers Publication Library
| Utbildning | Forskning | Styrkeområden | Om Chalmers | In English In English Ej inloggad.

Possibilities and constraints of implementing starch consolidated high speed steel in prototyping

Henrik Borgström (Institutionen för material- och tillverkningsteknik, Yt- och mikrostrukturteknik) ; P. Harlin ; M. Olsson ; T. Paiar ; Y. Wang ; Lars Nyborg (Institutionen för material- och tillverkningsteknik)
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING (0921-5093 ). Vol. 475 (2006), 1-2, p. 34-38.
[Konferensbidrag, refereegranskat]

In the starch consolidation (SC) process, a water-based slurry containing powder, starch, dispersant and thickener is used to fabricate near net-shape green bodies that are de-binded and further consolidated by sintering. In this study, gas atomized M3/2 as well as high and low carbon V-rich M4 type high speed steel powder (<150 mu m) are considered, Both material types undergo high volumetric shrinkage during super-solidus liquid phase sintering enabling them to reach near full density. The analyses and the review cover different process aspects like: recipe optimisation, post-gelatinization drying, de-binding and sintering. A SC recipe consisting of 58 vol.% powder, 3 vol.% starch, 1 vol.% dispersant and a thickener solution resulted in a density of >98% than what is theoretically stated after sintering. It is found that the success of the post-gelatinization drying procedure depends on the smoothness of mould material and controlling powder oxidation. The best combination was freeze drying the slurry in a silicon rubber mould. For V-rich alloys a total or partial control of eutectic carbides in the final microstructure could be realized for vacuum and nitrogen sintering atmospheres, respectively.

Nyckelord: starch consolidation, prototyping, super-solidus liquid phase sintering



Denna post skapades 2009-10-20. Senast ändrad 2010-03-25.
CPL Pubid: 100396

 

Läs direkt!


Länk till annan sajt (kan kräva inloggning)