Effect of metal particle size and powder volume fraction on the filling performance of powder injection moulded parts with a microtextured surface

Publikationen: Beitrag in FachzeitschriftArtikelForschung(peer-reviewed)

Externe Organisationseinheiten

  • Karelia University of Applied Sciences
  • University of Eastern Finland, Kuopio

Abstract

Metal injection moulding of miniaturized devices demands unique feedstock materials and mould designs with high dimensional accuracy. In this work, the influences of the powder size and powder content of 17–4 PH stainless steel feedstock and the influence of mould design on the successful production of micro-scaled structures were investigated. Ni mould inserts with high dimensional accuracy and texture sizes of 50–200 μm using a new microtexturing technique were manufactured. 17–4 PH stainless steel feedstocks with powder sizes (D 90) of 10 and 22 μm and powder contents of 60 and 65 vol.-% were compounded. The rheological properties of the obtained feedstocks were characterized with a capillary rheometer to assess their flowability. The results showed that 10 μm sized particles caused a slight but not significant increase in the viscosity. The highest viscosity increase occurred when the powder content increased from 60 to 65 vol.-%. Feedstocks with the 10 μm powder particles ensured complete filling within microtextures for all mould variations. However, when using feedstocks with 22 μm particles, the filling capabilities of the 50 and 100 μm microtextures decreased with increasing powder content. The shape retention was better for those micropillars produced with mould inserts with 200 μm cavities than for the micropillars replicated with the inserts having cavities of 50 and 100 μm. The results indicated that the proposed mould insert preparation technique opens new possibilities for mass production using the μMIM process to create micro-scaled components using feedstocks without nanoparticles.

Details

OriginalspracheEnglisch
Seiten (von - bis)604-612
Seitenumfang9
FachzeitschriftPrecision Engineering
Jahrgang72.2021
AusgabenummerNovember
Frühes Online-Datum6 Jul 2021
DOIs
StatusVeröffentlicht - Nov 2021