Ceramic shell fabrication via Stereo Lithography Apparatus: Recent progress on cracking problems and preventive measures

Abstract

Stereo Lithography Apparatus (SLA) has demonstrated improvements on surface-roughness and dimensional-accuracy of the precision casting prototypes in recent years, which however is still far from being satisfactory in industrial. One primary problem is the easy crack of the ceramic shell at sintering process originated from the high thermal expansion coefficient of the photosensitive resin. Herein, this paper aims to find a solution for the cracking problem of the SLA-prototyped ceramic shells. This paper introduces recent studies mainly focusing on the aspect of photosensitive resin modification, the hollow structure improvement inside the photosensitive resin prototype, the wax sheet pasting method on the weak part of ceramic shells, and the sintering process design of the photosensitive resin in ceramic shells. The performance of ceramic shells through these studies are evaluated, and a fundamental solution to the cracking problem of ceramic shells is thereafter prospected.

Keywords

• Investment casting
• 3D printing
• Cracking problem
• SLA phototype
• Sintering process