Hot chamber diecasting with Si3N4 ceramic injection system

Application to aluminium alloy components

Mitsuhiro Okayasu, M. Hitomi, H. Yamazaki

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Although hot chamber diecasting is an appropriate technology for producing high quality cast components, there are material limitations; at the process temperature, aluminium alloy erodes the immersed steel shot sleeve and plunger. Attempts have been made to employ a Si3N4 ceramic in place of steel. High quality Al hot chamber diecast components can be manufactured in this manner, but long production runs are not possible because failures occur in the ceramic sleeve even after, for example, a few thousand shots. The fracture in the ceramic sleeve is caused by high stresses arising from the plunger galling the sleeve surface owing to penetration of the Al alloy into the gap between the sleeve and plunger. The infiltrated Al alloy has been found to react chemically with the ceramics; silicon in the ceramic reacts with iron particles present as inclusions in the Al alloy. Hence, the purity of the molten Al alloy in the crucible is a significant factor in the production of high quality diecast components. To prevent penetration of the Al alloy, the injection system is cleaned periodically using hydrochloric acid, which dissolves the infiltrated Al alloy. Since etching by HCl can reduce the strength of the ceramic parts, this cleaning process must also be reconsidered. Recommendations to improve the quality of hot chamber diecast Al components are proposed.

Original languageEnglish
Pages (from-to)339-348
Number of pages10
JournalInternational Journal of Cast Metals Research
Volume21
Issue number5
DOIs
Publication statusPublished - Oct 2008
Externally publishedYes

Fingerprint

Aluminum alloys
Steel
Hydrochloric Acid
Crucibles
Silicon
Hydrochloric acid
silicon nitride
Molten materials
Etching
Cleaning
Iron
Temperature

Keywords

  • Aluminium alloy
  • Ceramic sleeve
  • Hot chamber diecasting
  • Liquid metal corrosion
  • Silicon nitride

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Metals and Alloys

Cite this

Hot chamber diecasting with Si3N4 ceramic injection system : Application to aluminium alloy components. / Okayasu, Mitsuhiro; Hitomi, M.; Yamazaki, H.

In: International Journal of Cast Metals Research, Vol. 21, No. 5, 10.2008, p. 339-348.

Research output: Contribution to journalArticle

@article{041b5b5e20314508b97b91b37e1fe060,
title = "Hot chamber diecasting with Si3N4 ceramic injection system: Application to aluminium alloy components",
abstract = "Although hot chamber diecasting is an appropriate technology for producing high quality cast components, there are material limitations; at the process temperature, aluminium alloy erodes the immersed steel shot sleeve and plunger. Attempts have been made to employ a Si3N4 ceramic in place of steel. High quality Al hot chamber diecast components can be manufactured in this manner, but long production runs are not possible because failures occur in the ceramic sleeve even after, for example, a few thousand shots. The fracture in the ceramic sleeve is caused by high stresses arising from the plunger galling the sleeve surface owing to penetration of the Al alloy into the gap between the sleeve and plunger. The infiltrated Al alloy has been found to react chemically with the ceramics; silicon in the ceramic reacts with iron particles present as inclusions in the Al alloy. Hence, the purity of the molten Al alloy in the crucible is a significant factor in the production of high quality diecast components. To prevent penetration of the Al alloy, the injection system is cleaned periodically using hydrochloric acid, which dissolves the infiltrated Al alloy. Since etching by HCl can reduce the strength of the ceramic parts, this cleaning process must also be reconsidered. Recommendations to improve the quality of hot chamber diecast Al components are proposed.",
keywords = "Aluminium alloy, Ceramic sleeve, Hot chamber diecasting, Liquid metal corrosion, Silicon nitride",
author = "Mitsuhiro Okayasu and M. Hitomi and H. Yamazaki",
year = "2008",
month = "10",
doi = "10.1179/136404608X320715",
language = "English",
volume = "21",
pages = "339--348",
journal = "International Journal of Cast Metals Research",
issn = "1364-0461",
publisher = "Maney Publishing",
number = "5",

}

TY - JOUR

T1 - Hot chamber diecasting with Si3N4 ceramic injection system

T2 - Application to aluminium alloy components

AU - Okayasu, Mitsuhiro

AU - Hitomi, M.

AU - Yamazaki, H.

PY - 2008/10

Y1 - 2008/10

N2 - Although hot chamber diecasting is an appropriate technology for producing high quality cast components, there are material limitations; at the process temperature, aluminium alloy erodes the immersed steel shot sleeve and plunger. Attempts have been made to employ a Si3N4 ceramic in place of steel. High quality Al hot chamber diecast components can be manufactured in this manner, but long production runs are not possible because failures occur in the ceramic sleeve even after, for example, a few thousand shots. The fracture in the ceramic sleeve is caused by high stresses arising from the plunger galling the sleeve surface owing to penetration of the Al alloy into the gap between the sleeve and plunger. The infiltrated Al alloy has been found to react chemically with the ceramics; silicon in the ceramic reacts with iron particles present as inclusions in the Al alloy. Hence, the purity of the molten Al alloy in the crucible is a significant factor in the production of high quality diecast components. To prevent penetration of the Al alloy, the injection system is cleaned periodically using hydrochloric acid, which dissolves the infiltrated Al alloy. Since etching by HCl can reduce the strength of the ceramic parts, this cleaning process must also be reconsidered. Recommendations to improve the quality of hot chamber diecast Al components are proposed.

AB - Although hot chamber diecasting is an appropriate technology for producing high quality cast components, there are material limitations; at the process temperature, aluminium alloy erodes the immersed steel shot sleeve and plunger. Attempts have been made to employ a Si3N4 ceramic in place of steel. High quality Al hot chamber diecast components can be manufactured in this manner, but long production runs are not possible because failures occur in the ceramic sleeve even after, for example, a few thousand shots. The fracture in the ceramic sleeve is caused by high stresses arising from the plunger galling the sleeve surface owing to penetration of the Al alloy into the gap between the sleeve and plunger. The infiltrated Al alloy has been found to react chemically with the ceramics; silicon in the ceramic reacts with iron particles present as inclusions in the Al alloy. Hence, the purity of the molten Al alloy in the crucible is a significant factor in the production of high quality diecast components. To prevent penetration of the Al alloy, the injection system is cleaned periodically using hydrochloric acid, which dissolves the infiltrated Al alloy. Since etching by HCl can reduce the strength of the ceramic parts, this cleaning process must also be reconsidered. Recommendations to improve the quality of hot chamber diecast Al components are proposed.

KW - Aluminium alloy

KW - Ceramic sleeve

KW - Hot chamber diecasting

KW - Liquid metal corrosion

KW - Silicon nitride

UR - http://www.scopus.com/inward/record.url?scp=55549119257&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=55549119257&partnerID=8YFLogxK

U2 - 10.1179/136404608X320715

DO - 10.1179/136404608X320715

M3 - Article

VL - 21

SP - 339

EP - 348

JO - International Journal of Cast Metals Research

JF - International Journal of Cast Metals Research

SN - 1364-0461

IS - 5

ER -