Original Date: 11/03/1996
Revision Date: 01/18/2007

Oak Ridge Centers for Manufacturing Technology’s (ORCMT) Work-for-Others (WFO) program extensively uses 1/4-scale, nickel-aluminum bronze cast components for testing. Currently, non-Department of Energy (DOE) vendors may take up to 26 weeks to sandcast a component before sending it to ORCMT for machining. These castings typically have incorrect or inconsistent dimensions; contain internal voids and porosity; or display defects during the machining process which require extensive rework. ORCMT has developed a nickel-aluminum bronze casting process which can create quick, practical, high-quality, 1/4-scale castings.

ORCMT’s nickel-aluminum bronze casting process involves creating a solid-part model which is used to produce multiple piece molds; electronically modeling the casting process via ProCast and making any necessary modifications to the model; producing numerical control tapes for machining the mold; machining the graphite molds; and pouring the casting by using a graphite system in a vacuum. ORCMT has demonstrated its casting process on a 1/4-scale propeller blade and produced a reusable graphite mold. X-ray analysis verified that the finished cast contained no internal voids or porosity. In addition, the process eliminated or minimized dead parts, weld repairs, machining probes, setups, and inspections.

ORCMT will be working with the Navy on additional casting and inverse-heat-conduction studies in support of the New Attack Submarine propulsor development. These studies will include solidification studies of sub-scale components; solidification studies and riser/gating design of the complete propulsor; and experimental design and data reduction for defining monoblock casting heat-transfer coefficients.

For more information see the Point of Contact for this survey.