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Title: Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold

Abstract

Hot-tearing is a major casting defect that is often difficult to characterize, especially for multicomponent Al alloys used for cylinder head castings. The susceptibility of multicomponent Al-Cu alloys to hot-tearing during permanent mold casting was investigated using a constrained permanent mold in which the load and displacement was measured. The experimental results for hot tearing susceptibility are compared with those obtained from a hot-tearing criterion based temperature range evaluated at fraction solids of 0.87 and 0.94. The Cu composition was varied from approximately 5 to 8 pct. (weight). Casting experiments were conducted without grain refining. The measured load during casting can be used to indicate the severity of hot tearing. However, when small hot-tears are present, the load variation cannot be used to detect and assess hot-tearing susceptibility.

Authors:
 [1];  [2];  [2];  [3];  [3];  [1];  [1];  [4]
  1. ORNL
  2. Fiat Chrysler Automobiles North America
  3. Worcester Polytechnic Institute (WPI), MA
  4. Nemak, Garza Garcia, N.L., Mexico
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
Work for Others (WFO)
OSTI Identifier:
1348325
DOE Contract Number:
AC05-00OR22725
Resource Type:
Conference
Resource Relation:
Conference: TMS 2017 146th Annual Meeting and Exhibition, San Diego, CA, USA, 20170226, 20170226
Country of Publication:
United States
Language:
English

Citation Formats

Sabau, Adrian S, Mirmiran, Seyed, Glaspie, Christopher, Li, Shimin, Apelian, Diran, Shyam, Amit, Haynes, James A, and Rodriguez, Andres. Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold. United States: N. p., 2017. Web. doi:10.1007/978-3-319-51493-2_44.
Sabau, Adrian S, Mirmiran, Seyed, Glaspie, Christopher, Li, Shimin, Apelian, Diran, Shyam, Amit, Haynes, James A, & Rodriguez, Andres. Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold. United States. doi:10.1007/978-3-319-51493-2_44.
Sabau, Adrian S, Mirmiran, Seyed, Glaspie, Christopher, Li, Shimin, Apelian, Diran, Shyam, Amit, Haynes, James A, and Rodriguez, Andres. Sun . "Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold". United States. doi:10.1007/978-3-319-51493-2_44. https://www.osti.gov/servlets/purl/1348325.
@article{osti_1348325,
title = {Hot-tearing of multicomponent Al-Cu alloys based on casting load measurements in a constrained permanent mold},
author = {Sabau, Adrian S and Mirmiran, Seyed and Glaspie, Christopher and Li, Shimin and Apelian, Diran and Shyam, Amit and Haynes, James A and Rodriguez, Andres},
abstractNote = {Hot-tearing is a major casting defect that is often difficult to characterize, especially for multicomponent Al alloys used for cylinder head castings. The susceptibility of multicomponent Al-Cu alloys to hot-tearing during permanent mold casting was investigated using a constrained permanent mold in which the load and displacement was measured. The experimental results for hot tearing susceptibility are compared with those obtained from a hot-tearing criterion based temperature range evaluated at fraction solids of 0.87 and 0.94. The Cu composition was varied from approximately 5 to 8 pct. (weight). Casting experiments were conducted without grain refining. The measured load during casting can be used to indicate the severity of hot tearing. However, when small hot-tears are present, the load variation cannot be used to detect and assess hot-tearing susceptibility.},
doi = {10.1007/978-3-319-51493-2_44},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2017},
month = {Sun Jan 01 00:00:00 EST 2017}
}

Conference:
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  • Heat transfer between a solidifying casting and the mold is critical for achievement of high quality in the cast product. This is especially important in permanent mold casting where the rate limiting steps for heat transfer between the casting and the mold are primarily controlled by conditions at the mold-metal interface. The mold-metal interface is emphasized, since as the casting solidifies, it tends to shrink which creates areas where gaps form between the casting and the mold surface. Quantification of these conditions is key to modeling of permanent mold casting solidification. The focus of this paper is directed to methodsmore » for determination of metal/mold heat transfer. A description of the application of the Inverse Heat Conduction Problem to determine the interfacial heat transfer coefficients from temperature histories at interior points is presented. This approach is supported by conditions which allow use of quasi steady-state approximations for determination of time-dependent heat transfer coefficients. The use of heat transfer coefficient analyses for permanent mold casting are describes and the limitations defined. The need for further effort in this area is presented, and areas for future work are defined.« less
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