A Design Methodology for Casting Ladle to Minimize Air Entrapment and Oxide Inclusion: An Application to Permanent Mold Casting Process

For thin-walled casting development of austempered ductile iron (ADI), permanent mold casting and accompanied heat treatment practice were systematically investigated to suppress and/or remove chill defects of ductile cast iron (DCI) with various thickness of 2 to 9 mm and to ensure mechanical properties of the final ADI casting. Si content was increased up to 3.8% to reduce the chill formation tendency under a high cooling rate. The residual Mg content remarkably affected the nodule count, while the nodule size and spherodization were proven to have weak relationships. Austenitizing process followed by austempering was very sensitive to chemical compositions (Si and Sn) and heat treatment temperature. As a practical application, the steel bar coupler for a structural frame was tried to produce without subsequent machining.

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Properties and CA4GE-Engine Test of TiAl-Based Alloy Valves by Permanent Mold Casting

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.557 ◽

2010 ◽

Vol 139-141 ◽

pp. 557-560

Author(s):

Wen Bin Sheng ◽

Chun Xue Ma ◽

Wan Li Gu

Keyword(s):

Tial Alloy ◽

Centrifugal Casting ◽

Casting Process ◽

Vacuum Arc ◽

Permanent Mold ◽

Casting Method ◽

Arc Melting ◽

Vacuum Arc Melting ◽

Mold Casting ◽

Induction Skull Melting

TiAl-based alloy valves were manufactured by combining charges compressed /vacuum arc melting (VA)/ induction skull melting (ISM) procedure with permanent mold centrifugal casting method. Microstructures, compositions and mechanical properties of as-cast and hot isostatical pressed (HIPed) valves are detected. Results show that the permanent mold centrifugal casting process obviously refines the size of grain in TiAl alloy and the tensile strength of as-cast and HIPed valves are 550MPa and 580MPa at 20°C, 370MPa and 470MPa at 815°C, respectively. As-cast specimens show ~0% elongation at 20°C and 1~2% at 815°C, while HIPed ones show an elongation of 1~2% at room temperature and about 10% at 815°C. Furthermore, a 200-hour test was carried out with CA4GE-engine, which demonstrated the possibility of as-cast TiAl alloy valves for the substitution of present steel ones.

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Permanent Mold Casting Practice and Microstructure and Mechanical Properties of Thin-Sectioned ADI Casting

Advanced Materials Research - Advanced Materials and Processing ◽

10.4028/0-87849-463-4.531 ◽

2007 ◽

pp. 531-534

Author(s):

B.M. Moon ◽

B.H. Kim ◽

J.S. Shin ◽

S.M. Lee

Keyword(s):

Mechanical Properties ◽

Permanent Mold ◽

Permanent Mold Casting ◽

Microstructure And Mechanical Properties ◽

Mold Casting

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Permanent Mold Casting

Casting ◽

10.31399/asm.hb.v15.a0005260 ◽

2008 ◽

pp. 689-699

Keyword(s):

Permanent Mold ◽

Permanent Mold Casting ◽

Mold Casting

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Magnesium Permanent Mold Castings Optimization

Materials Science Forum ◽

10.4028/www.scientific.net/msf.690.65 ◽

2011 ◽

Vol 690 ◽

pp. 65-68 ◽

Cited By ~ 51

Author(s):

Fady Refaat Elsayed ◽

Norbert Hort ◽

Mario Alberto Salgado Ordorica ◽

Karl Ulrich Kainer

Keyword(s):

Magnesium Alloys ◽

Casting Process ◽

Mold Temperature ◽

Holding Time ◽

Permanent Mold ◽

Melt Temperature ◽

Cast Part ◽

Mold Casting ◽

Permanent Mold Castings ◽

Inhomogeneous Properties

Permanent mold casting is a well-established route for casting large magnesium alloys components. Casting parameters like superheat, mold temperature, and holding time can often result in inhomogeneous properties, porosity, and segregation problems in the cast part. In order to optimize the casting process, control of the casting parameters including mold temperatures and holding times is essential to promote directional solidification, and ensure defect free homogenous structure. Binary Mg-9wt.%Al and Mg-10wt.%Gd alloys were used to investigate the effect of casting parameters such as melt temperature and holding time on the part macro and microstructure.

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