Premium
Particle Packing in Ceramic Injection Molding
Author(s) -
Wright Jadith K.,
Edirisinghe Mohan J.,
Zhang Jian G.,
Evans Julian R. G.
Publication year - 1990
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1990.tb06742.x
Subject(s) - shrinkage , volume fraction , ceramic , materials science , pyrolysis , volume (thermodynamics) , viscosity , composite material , pyrolytic carbon , molding (decorative) , particle (ecology) , fraction (chemistry) , chemical engineering , thermodynamics , chemistry , chromatography , oceanography , physics , engineering , geology
The shrinkage of ceramic injection molding suspensions caused by pyrolytic removal of the organic vehicle was measured for initial ceramic volume fractions from 0.48 to 0.64. Shrinkage was inversely related to initial ceramic volume fraction V , and maximum volume fraction after pyrolysis V *, max was 0.65. The factors which restrict shrinkage are discussed. The maximum volume fraction, obtained from semiempirical equations relating the viscosity of suspensions to volume fraction of powder ( V max ) was 0.73 to 0.76. Both the viscosity of the suspensions and the shrinkage on removal of the organic vehicle can be interpreted in terms of a free volume of fluid over and above that needed to fill interstices between contacting particles. Thermomechanical measurements also show that the free‐volume concept helps to interpret the transition from fluid to quasi‐solid properties as the organic vehicle is removed by pyrolysis from a molded body.