Micro injection molding of micro gear using nano-sized zirconia powder

Abstract

Powder injection molding (PIM) is well established in macro molding. Scaling down to micro-PIM (lPIM) opens a new arena for cost effective production of micro components. One potential application is the manufacture of cutting tools with sharp edges for machining. However, scaling down to such a level produces challenges in raw material preparation, injection molding and thermal treatment. In this report, near dense ([98% of theoretical density) tensile bars and 3 mm micro gears were produced using 50 nm Yttria Tetragonal Zirconia Polycrystal (Y-TZP). The sintered gear teeth were well defined and visually defect free.

New methacrylate-based feedstock systems for micro powder injection moulding

“…Micro injection moulding applying a feedstock consisting of a polyethylene/wax binder, stearic acid as dispersant and 50 vol.% zirconia (same type) delivered a density of 98.2% of the theoretical value . Similar results ([98%) were obtained by Jardiel (Jardiel et al 2008) as well as by Yu and coworkers applying different zirconia containing feedstock mixtures suitable for injection moulding (Yu et al 2009). …”

Effect of Injection Molding and Sintering Behaviors on Y-TZP Dental Implants

“…The first and second binder vaporization periods respectively took place at temperatures between 260 to 380°C and 400 to 500°C, as evidenced by the obvious weight changes at these temperatures. Within these temperature periods, the heating rates should be slower to ensure enough time to eliminate the binder [12,13].…”

A review of micro-powder injection moulding as a microfabrication technique

“…Part densities of metal and ceramic parts were measured using the Archimedes principle using deionized water as the immersion medium [10,27,83], where weights were measured to 0.1 mg [10].…”