Wai Yee Yeong

Aerosol jet printed pH sensor based on carbon nanotubes for flexible electronics

The monitoring of pH is valuable for many environmental, industrial, and biological applications. Here, we develop a flexible pH sensor using CNT material using aerosol jet technology. The chemiresistive pH sensor is fabricated with a CNT-based miniaturized serpentine sensing element printed on top of the silver electrodes. Aerosol jet printing parameters are optimized to achieve high resolution printing. The fabricated pH sensor shows good sensitivity and repeatability.

High resolution aerosol jet printing of conductive ink for stretchable electronics

Stretchable electronics is gaining wide spread attention due to its application in many applications such as wearable devices, soft robotics, biomedical and consumer products. Aerosol jet printing, which is capable of printing very fine features, can be used to fabricate high performance flexible electronic devices. In this paper, we explore aerosol jet process technique to print conductive stretchable ink for fabricating new-age electronic circuits. Functional composite ink made of silicone and silver composite were used to print directly on stretchable silicone rubber substrate. Electronic functional devices such as flexible circuit and strain gauge were successfully printed, characterized and tested for stretchability.

Effect of heat treatment on cobalt-chromium-molybdenum alloy fabricated by selective laser melting

Cobalt-chromium-molybdenum (CoCrMo) alloys have excellent corrosion resistance, biocompatibility and strength. As such, they have been widely used in dental applications, such as removable partial dentures, metal frames, customized abutments, crowns and bridges in the anterior and posterior regions. The capability of selective laser melting (SLM), a powder bed fusion additive manufacturing process, to produce customizable products have led to extensive research of using this process for applications in the biomedical field. Several works have been reported on the production of CoCrMo alloys using SLM for various implants. However, there is still limited information on the effect of post process heat treatment on SLM CoCrMo alloys. In this paper, ASTM F75 CoCrMo alloy is fabricated using SLM and underwent heat treatment originally designed for casted ASTM F75 CoCrMo alloy. The mechanical properties of heat treated SLM produced CoCrMo parts are reported and benchmarked against their casted counterparts.