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Karlsruhe Nano Micro Facility
KIT-Campus North

Building 440

H.-von-Helmholtz-Platz 1

76344 Eggenstein-Leopoldshafen, Germany

 

phone: +49(721)608-23123

fax: +49(721)608-26273

knmf-userofficeOie2∂kit edu

User Office

KNMF Profile

Injection Moulding (IM)

KNMF Laboratory for Micro- and Nanostructuring

Injection moulding allows the high economic mass fabrication of complex-shaped nano and micro components. These can be singular items or large bodies with nano- or microstructures on the surface, respectively. In both cases very high geometric accuracies and smallest tolerances can be achieved using e.g. LIGA-fabricated mould inserts. Besides the replication of polymers powder injection moulding (MicroPIM) allows for the micro fabrication of components made of a large variety of metals or ceramics. Having reached a reliable status, two-component injection moulding and inmould-labelling reveal strong advantages with respect to reduced mounting expenditures and the capability to produce multi-functional devices.

Download technology description (PDF)

Contact

Dr. Volker Piotter

Phone +49 721 608-26463
Fax +49 721 608-22095
Email volker piotterLdj3∂kit edu
Institute for Applied Materials (IAM-WPT) - www.iam.kit.edu/wpt/english

Features

  • Cycle times < 3 s – 6 min
  • Largest replicated aspect ratio:
    - 17 for free standing structure (height: 2000 μm; width: 115 μm)
    - 25 for buried structure (height: 250 μm; width: 10 μm)
  • Smallest replicated structural detail: < 100 nm for aspect ratio 1, in case of lower aspect ratio replication minima decrease correspondingly
  • Special variants like compression injection moulding for enhanced accuracies
  • Fabrication of metal and ceramic parts via powder injection moulding
  • Multifunctional parts by two-component or inmould-labelling powder injection moulding
  • Special equipment for designing/developing feedstock compositions
  • Special equipment for thermal treatment available, e. g. hot isostatic pressing (HIP) applying temperature and pressure parameters on a worldwide unique high level

Limitations/constraints

  • Relatively large efforts for tooling necessary
  • Replication process very sensitive to mould insert’s surface roughness
  • Side wall draft angle or ejector slope is recommended for larger aspect ratios depending on the mould insert’s roughness
  • Limited undercuts
  • No hollow parts in one step fabrication possible

Materials

  • 1- and 2-component injection moulding with polymers, metals , and ceramics
  • Polymers: nearly all thermoplastics and thermoplastic elastomers
  • Functional polymer-based nanocomposites with improved optical, dielectric or conductive properties (e. g. PMMA/CNT, PC/Al2O3 a. o.)
  • Feedstock development for customer-specific materials using e.g. nano-sized powders
  • Metals: PM steels like 17-4PH and 316L, Cu, W and W-alloys, hard metals
  • Ceramics: oxide ceramics like ZrO2 and Al2O3, Si3N4, mixture ceramics like TiN-Al2O3 with defined material properties, e.g. electrical conductivity
  • Subsequent densification and reduction of porosity by HIP

Typical structures and designs

Figure 1

Fig. 1: Smallest puzzle of the world whose pieces have been made of PMMA using singular LIGA mould inserts.

 

Figure 2

Fig. 2: SEM figure of polymer part (PMMA) with nano-sized structures made by injection moulding. (Länge ≙ length).

 

Figure 3

Fig. 3: SEM-picture of pure tungsten after sintering (above), the same material after additional HIP densification showing significantly reduced porosity (below).

 

Figure 4

Fig. 4: Gear wheel/shaft sample made by two-component injection moulding of alumina (shaft) and zirconia ceramic (gear wheel). Combined sintered part (left) and green body (right).

 

Figure 5

Fig. 5: Ring gear of planetary gear set, 1.4542.