Fabrication of zirconia-toughened alumina parts by powder injection molding process: Optimized processing parameters

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Zirconia-toughened alumina (ZTA) parts were fabricated by using a powder injection molding process that utilizes a multi-component binder system based on high-density polyethylene, paraffin wax, and stearic acid. The entire aspect of the manufacturing process, which includes mixing, injection molding, debinding, and sintering, were optimized in this study. ZTA powder was mixed with binders at powder loading ranging from 53 vol% to 59 vol%. The optimum powder loading was determined by analyzing the rheological properties and homogeneity of feedstocks. During injection molding, the temperature and injection pressure parameters were manipulated to obtain optimum density results. A two-stage debinding process (solvent and thermal) was used to remove binders in green parts. Debound parts were sintered at temperatures ranging from 1400 C to 1600 C for 2 h. The shrinkage, density, and hardness of the sintered parts were measured. Results show that with homogeneous mixing, the feedstocks were transformed into pseudoplastic in less than 30 min. Powder loading of 57 vol% is the most optimal case for injection molding according to the power law index and flow activation energy values. The theoretical relative density reached 90.27% with defect-free parts under optimum injection temperature and pressure. The weights of the parts decreased by 82.26% during solvent debinding at 60 C, whereas the binders were completely degraded at approximately 550 C during thermal debinding. Experimental results also indicate that the shrinkage, density, and hardness reached their maximum values at a sintering temperature of 1600 C. The sintered parts were densified with approximately 98% theoretical density, hardness of 1582.4 HV, and 15% shrinkage value.

Original languageEnglish
Pages (from-to)273-280
Number of pages8
JournalCeramics International
Volume40
Issue number1 PART A
DOIs
Publication statusPublished - Jan 2014

Fingerprint

Aluminum Oxide
Injection molding
Zirconia
Powders
Alumina
Binders
Fabrication
Processing
Hardness
Feedstocks
Sintering
Paraffin waxes
Temperature
Stearic acid
Polyethylene
High density polyethylenes
Activation energy
zirconium oxide
Defects
Hot Temperature

Keywords

  • A. Injection molding
  • A. Mixing
  • C. Mechanical properties
  • Zirconia-toughened alumina

ASJC Scopus subject areas

  • Ceramics and Composites
  • Process Chemistry and Technology
  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Materials Chemistry

Cite this

@article{bd6c6c750d884130903a65ed1ff12218,
title = "Fabrication of zirconia-toughened alumina parts by powder injection molding process: Optimized processing parameters",
abstract = "Zirconia-toughened alumina (ZTA) parts were fabricated by using a powder injection molding process that utilizes a multi-component binder system based on high-density polyethylene, paraffin wax, and stearic acid. The entire aspect of the manufacturing process, which includes mixing, injection molding, debinding, and sintering, were optimized in this study. ZTA powder was mixed with binders at powder loading ranging from 53 vol{\%} to 59 vol{\%}. The optimum powder loading was determined by analyzing the rheological properties and homogeneity of feedstocks. During injection molding, the temperature and injection pressure parameters were manipulated to obtain optimum density results. A two-stage debinding process (solvent and thermal) was used to remove binders in green parts. Debound parts were sintered at temperatures ranging from 1400 C to 1600 C for 2 h. The shrinkage, density, and hardness of the sintered parts were measured. Results show that with homogeneous mixing, the feedstocks were transformed into pseudoplastic in less than 30 min. Powder loading of 57 vol{\%} is the most optimal case for injection molding according to the power law index and flow activation energy values. The theoretical relative density reached 90.27{\%} with defect-free parts under optimum injection temperature and pressure. The weights of the parts decreased by 82.26{\%} during solvent debinding at 60 C, whereas the binders were completely degraded at approximately 550 C during thermal debinding. Experimental results also indicate that the shrinkage, density, and hardness reached their maximum values at a sintering temperature of 1600 C. The sintered parts were densified with approximately 98{\%} theoretical density, hardness of 1582.4 HV, and 15{\%} shrinkage value.",
keywords = "A. Injection molding, A. Mixing, C. Mechanical properties, Zirconia-toughened alumina",
author = "{Md Ani}, Sarizal and Andanastuti Muchtar and Norhamidi Muhamad and {A Ghani}, Jaharah",
year = "2014",
month = "1",
doi = "10.1016/j.ceramint.2013.05.134",
language = "English",
volume = "40",
pages = "273--280",
journal = "Ceramics International",
issn = "0272-8842",
publisher = "Elsevier Limited",
number = "1 PART A",

}

TY - JOUR

T1 - Fabrication of zirconia-toughened alumina parts by powder injection molding process

T2 - Optimized processing parameters

AU - Md Ani, Sarizal

AU - Muchtar, Andanastuti

AU - Muhamad, Norhamidi

AU - A Ghani, Jaharah

PY - 2014/1

Y1 - 2014/1

N2 - Zirconia-toughened alumina (ZTA) parts were fabricated by using a powder injection molding process that utilizes a multi-component binder system based on high-density polyethylene, paraffin wax, and stearic acid. The entire aspect of the manufacturing process, which includes mixing, injection molding, debinding, and sintering, were optimized in this study. ZTA powder was mixed with binders at powder loading ranging from 53 vol% to 59 vol%. The optimum powder loading was determined by analyzing the rheological properties and homogeneity of feedstocks. During injection molding, the temperature and injection pressure parameters were manipulated to obtain optimum density results. A two-stage debinding process (solvent and thermal) was used to remove binders in green parts. Debound parts were sintered at temperatures ranging from 1400 C to 1600 C for 2 h. The shrinkage, density, and hardness of the sintered parts were measured. Results show that with homogeneous mixing, the feedstocks were transformed into pseudoplastic in less than 30 min. Powder loading of 57 vol% is the most optimal case for injection molding according to the power law index and flow activation energy values. The theoretical relative density reached 90.27% with defect-free parts under optimum injection temperature and pressure. The weights of the parts decreased by 82.26% during solvent debinding at 60 C, whereas the binders were completely degraded at approximately 550 C during thermal debinding. Experimental results also indicate that the shrinkage, density, and hardness reached their maximum values at a sintering temperature of 1600 C. The sintered parts were densified with approximately 98% theoretical density, hardness of 1582.4 HV, and 15% shrinkage value.

AB - Zirconia-toughened alumina (ZTA) parts were fabricated by using a powder injection molding process that utilizes a multi-component binder system based on high-density polyethylene, paraffin wax, and stearic acid. The entire aspect of the manufacturing process, which includes mixing, injection molding, debinding, and sintering, were optimized in this study. ZTA powder was mixed with binders at powder loading ranging from 53 vol% to 59 vol%. The optimum powder loading was determined by analyzing the rheological properties and homogeneity of feedstocks. During injection molding, the temperature and injection pressure parameters were manipulated to obtain optimum density results. A two-stage debinding process (solvent and thermal) was used to remove binders in green parts. Debound parts were sintered at temperatures ranging from 1400 C to 1600 C for 2 h. The shrinkage, density, and hardness of the sintered parts were measured. Results show that with homogeneous mixing, the feedstocks were transformed into pseudoplastic in less than 30 min. Powder loading of 57 vol% is the most optimal case for injection molding according to the power law index and flow activation energy values. The theoretical relative density reached 90.27% with defect-free parts under optimum injection temperature and pressure. The weights of the parts decreased by 82.26% during solvent debinding at 60 C, whereas the binders were completely degraded at approximately 550 C during thermal debinding. Experimental results also indicate that the shrinkage, density, and hardness reached their maximum values at a sintering temperature of 1600 C. The sintered parts were densified with approximately 98% theoretical density, hardness of 1582.4 HV, and 15% shrinkage value.

KW - A. Injection molding

KW - A. Mixing

KW - C. Mechanical properties

KW - Zirconia-toughened alumina

UR - http://www.scopus.com/inward/record.url?scp=84887625652&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84887625652&partnerID=8YFLogxK

U2 - 10.1016/j.ceramint.2013.05.134

DO - 10.1016/j.ceramint.2013.05.134

M3 - Article

AN - SCOPUS:84887625652

VL - 40

SP - 273

EP - 280

JO - Ceramics International

JF - Ceramics International

SN - 0272-8842

IS - 1 PART A

ER -