Title: Yield improvement for lost mould rapid infiltration forming process by a multistage fractional factorial split plot design

Authors: Chumpol Yuangyai, Harriet Black Nembhard, Gregory Hayes, Nicholas Antolino, James H. Adair

Addresses: Harold and Inge Marcus Department of Industrial and Manufacturing Engineering, The Pennsylvania State University, 301 Leonhard Building, University Park, PA 16802, USA. ' Harold and Inge Marcus Department of Industrial and Manufacturing Engineering, The Pennsylvania State University, 301 Leonhard Building, University Park, PA 16802, USA. ' Department of Material Science and Engineering, The Pennsylvania State University, 224 Material Research Laboratory, University Park, PA 16802, USA. ' Department of Material Science and Engineering, The Pennsylvania State University, 224 Material Research Laboratory, University Park, PA 16802, USA. ' Department of Material Science and Engineering, The Pennsylvania State University, 224 Material Research Laboratory, University Park, PA 16802, USA

Abstract: Statistical design of experiments is widely used among scientists and engineers to understand influential factors in a laboratory or manufacturing process. One of the underlying principles of using the statistical design of experiments method is randomisation, each run of experimental settings will be determined completely unsystematically. In practice, especially in a complicated process that consists of multiple stages, randomisation may pose too high a burden on time and cost. In this study, the multistage fraction factorial split plot design is proposed for green yield improvement in a lost mould rapid infiltration process that has been developed to fabricate zirconia ceramic parts. This design allows a relaxation of the randomisation principle so that certain experimental runs can be carried out in convenient groups. The results indicate that the type of immersion chemical and mould coating play a role in improving process yield. Additionally, the results suggest that a mould infiltration machine should be used to improve the reproducibility of the process.

Keywords: split plot design; multistage experimentation; restricted randomisation; colloidal processing; zirconia; green yield improvement; mould infiltration forming; design of experiments; DOE; ceramic parts; nanomanufacturing.

DOI: 10.1504/IJNM.2009.027501

International Journal of Nanomanufacturing, 2009 Vol.3 No.4, pp.351 - 367

Published online: 28 Jul 2009 *

Full-text access for editors Access for subscribers Purchase this article Comment on this article