Control of the thermal properties of investment casting molds can be used to improve mold filing and control directional casting solidification. Experiments were performed to design a low thermal diffusivity investment casting mold through the use of hollow spherical refractory particles (cenospheres). The number of stucco layers in which the cenospheres were substituted for silica grain was an...

Abstract — Ceramic shell investment casting process is used to produce high quality metal products with relatively close dimensional tolerances. The refractory primary slurry that is applied to the surface of the pattern assembly, to pick up its surface details plays a very important role in ceramic shell investment casting process (CSICP). It produces a smooth, acceptable surface finish of the...

Two widely used jewellery investment casting alloys (platinum with 5 wt% ruthenium (Pt-5Ru) and platinum with 5 wt% cobalt (Pt-5Co)) suffer from poor castability and other drawbacks. In this work thermodynamic calculations of alloy properties were employed to optimise the alloy compositions. Segregation behaviour appeared to be important for the melting range. Scheil simulations were used to si...

The classical version of the differential allocation hypothesis states that, when females reproduce over their lifetime with partners that differ in their genetic quality, they should invest more in reproduction with high-quality males. However, in species with lifetime monogamy, such as the zebra finch, partner quality will typically remain the same. In this case, the compensatory investment (...

During the investment casting process, the shell is subjected to high internal pressure and thermal stress, particularly during pattern removal and when pouring steel into the free standing ceramic shell. Most testing methods investigate the properties of the ceramic shell in flat regions while cracks typically form in the sharp corners and edge regions. The corners and edge regions have differ...

Determining alloy shrinkage factors is very important for the investment casting process. Casting dimensions can be obtained from numerical simulations of heat transfer and deformation phenomena. The accuracy of the dimensional results depends on heat transfer results. In order to validate heat transfer models, temperature data were obtained during casting of aluminum alloy A356 in shell molds ...

OBJECTIVES Aim of the study was to analyze the mold filling capacity and the dimensional accuracy of a spinel-based investment for titanium castings. METHODS Expansion of the investment in dependence of the preheating temperature was measured in a dilatometer. The degree of transformation of MgO and Al2O3 to spinel (MgAl2O4) was evaluated by means of X-ray powder diffraction. Mold filling cap...