The newly designed vacuum differential pressure casting (VDPC) unit was introduced, by which the capability of the VDPC process to produce thin-walled complicated Al-alloy castings, that are free from oxides, gas pore and shrinkage cavity and thus enhance overall part quality, was studied. Experimental results were compared with those of traditional gravity pouring and vacuum suction casting. The first series of experiments were focused on investigating thecastability of thin section Al-alloy casting. In the second series of experiments the metallographic evidence, casting strength and soundness were examined. Finally, case studies of very interesting thin walled complicated casting applications were described. The advantages of the described technique have made possible to produce thin walled complicated Al-alloy casting (up to a section thickness of 1 mm), which is not practical for gravity pouring and vacuum suction casting.
used sodium silicate sand, dry reusing, wet reclaiming, Technology, Manufactures, and TS1-2301
Based on the characteristics of used sodium silicate sand and the different use requirements for recycled sand, "dry reusing and wet reclaiming of used sodium silicate sand" is considered as the most suitable technique for the used sand. When the recycled sand is used as support sand, the used sand is only reused by dry process including breaking, screening, dust-removal, etc., and it is not necessary that the used sand is reclaimed with strongly rubbing and scraping method, but when the recycled sand is used as facing sand (or single sand), the used sand must be reclaimed by wet method for higher removal rate of the residual binders. The characteristics and the properties of the dry reused sand are compared with the wet reclaimed sand after combining the different use requirements of support sand and facing sand (or single sand), and above the most adaptive scheme has also been validated.
Based on Vacuum Differential Pressure Casting (VDPC) precision forming technology and the Selective Laser Sintering (SLS) Rapid Prototyping (RP) technology, a rapid manufacturing method called Rapid Precision Casting (RPC) process from computer three-dimensional solid models to metallic parts was investigated. The experimental results showed that the main advantage of RPC was not only its ability to cast higher internal quality and more accurate complex thin-walled aluminum alloy parts, but also the greatly-reduced lead time cycle from Selective Laser Sintering(SLS) plastic prototyping to metallic parts. The key forming technology of RPC for complex thin-walled metallic parts has been developed for new casting production and Rapid Tooling (RT), and it is possible to rapidly manufacture high-quality and accurate metallic parts by means of RP in foundry industry.
rapid prototyping, selected laser sintering, laser scanning, part accuracy, Technology, Manufactures, and TS1-2301
The effects of different factors, including the precision of the selected laser sintering (SLS) equipment, sintering temperature, sintered thickness of individual layer and laser scanning route, on the SLS part accuracy have been analyzed and studied. Some measures are suggested in order to improve the part accuracy made by SLS.