Google Search

WWW   Northwestern   Dunand Group

Home | About Us | Contact Us | Site Map
| Photos | Videos |
| Prof. David Dunand | Dr. Dinc Erdeniz | Dr. Anthony De Luca | Dr. Christoph Kenel | Dr. Jacques Perrin Toinin | Dr. Amir R. Farkoosh | Shannon Taylor| Richard Michi | Tony Chung | Fernando Reyes | Francesca Long | Stephen Wilke | Kristen Scotti | Group Alumni |
| High Temperature Alloys | Metallic Foams | Cultural Heritage Materials |
| Searchable Literature Database | Journal Articles Sorted by Year of Publication | U.S. Patents |

Jens Sesseg

Tungsten micro-lattices are produced by direct ink writing of a slurry of WO3-0.5% NiO submicron powders, followed by H2 reduction and Ni-activated sintering. The green bodies undergo isotropic linear shrinkage of ~50% during the thermal treatments resulting in microlattices, with overall ~50% open porosity, consisting 95-100% dense tungsten struts ~100 µm in diameter. Ball-milling of the powders and inks reduces the sintering temperature needed to achieve full densification from 1400 to 1200 °C and enables the ink to be extruded through a 200 µm nozzle. Full sintering densification is achieved through the addition of 0.5 wt% NiO to the slurry, which was also beneficial for the following infiltration with liquid copper. Partially-sintered struts with submicron open porosity were also infiltrated with Cu, resulting in a co-continuous W/Cu composites with wide W struts/Cu channel at the lattice scale, and fine W/Cu interpenetrating skeletons at the strut scale. The project currently investigates possible mechanical advantages of using a gyroid structure instead of a lattice structure. The continuous geometry might be able to eliminate stress concentration and hence making the structure tougher, especially at lower temperatures where the material is brittle.

I was born and grew up in Switzerland and am studying materials science at the ETH in Zürich. Being fascinated by the possibilities additive manufacturing offers I decided that I’d like to explore the field and contribute to expand the possibilities. Hence I focused on this related topics during my studies.

Research

Additive manufacturing of tungsten by reduction and sintering

 

B.S., Materials Science, ETH Zürich

Contact

Phone: +41 79 220 39 19
Fax:  
e-mail:

jens.sesseg@northwestern.edu

Address:  

Select Honors

 

 

July 23, 2013