Formability of the Layer Additive Ceramic Part

Abstract

The material in powder state has long been used by selective laser sintering (SLS) for making rapid prototyping (RP) parts. A new approach to fabricate smoother surface roughness RP parts of ceramic material from slurry-sate has been developed in this study. The silica slurry was successfully laser-gelling in a self-developed laser sintering equipment. In order to overcome the insufficient bonding strength between layers, a strategy is proposed to generate ceramic parts from a single line, a single layer, to multi-layers of gelled cramic in this paper. It is found that when the overlap of each single line is 25% and the over-gel between layers is 30%, stronger and more accurate dimensional parts can be obtained under a laser power of 15W, a laser scanning speed of 250 mm/s, and a layer thickness of 0.1 mm. The 55:45 wt. % of the proportion between the silica powder and silica solution results in suitable viscosity of the ceramic slurries without precipitation. Furthermore, the effects of process parameters for the dimensional accuracy and surface roughness of the gelled parts are investigated and appropriate parameters are obtained.

Fabrication Inner Channel Ceramics Using Layer Additive Method

“…When the laser beam scans over a ceramic layer, the surface of the ceramic layer will adhere to the underlying portion of the previous cured ceramic layer. A cross section of a three dimensional part can be fabricated by this way [6,7].…”

Selective laser gelation of ceramic–matrix composites

“…When a silica sol is evaporated via the laser beam energy, the concentration of the sol is increased and the sol then yields the gel that links particles together to form 3D networks and to bridge the gap between particles. This procedure is referred to as ''gelation" [10,11].…”

Rapid Manufacturing of Metal-Ceramic Composites

“…As shown in Fig. 1, the SLG process comprises following steps: (a) mixing silica sol and metal powder as a slurry, (b) paving the slurry by a scraper onto the elevator platform to from a slurry layer, (c) gelling the slurry after selective irradiating via a Nd:YAG laser, therefore, a solid layer is formed, (d) lowering the platform with a layer thickness, (e) repeating steps (b) to (d), a multi-layer part is built by sequentially gelled layers, (f) removing the residual slurry around the part and then a 3D composite sample is finished [7].…”