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As a standard test-bar permanent mold, the ''Stahl'' Mold has been widely used in foundries to assess the properties of cast alloys. However, inferior mechanical properties are often obtained with this mold due to shrinkage-induced microporosity in the gage section. In order to improve the mechanical properties, a design modification comprising a thin knife ingate between the feeder and test-bar cavity was evaluated in this work. The new design was studied by computeraided simulation. Simulations predicted that the knife ingate improved the metal feeding capability and reduced the shrinkage microporosity at the gage section from 3 to 1 pct. Experimental verification work has been undertaken with aluminum alloy A356, and the results were analyzed by a statistics theory-based factorial analysis method. The new design resulted in main effects with ultimate tensile strength (UTS) improvement of 20 MPa (relative 12 pct) and elongation increment of 2 pct (relative 45 pct) for the as-cast test bars.

Many nonferrous metals, including aluminum, nickel, copper, and others, are among the few materials that do not degrade or lose their chemical or physical properties in the recycling process. As a result, these metals can be recycled an infinite number of times. This article focuses on the recycling of nonferrous alloys, namely, aluminum, copper, magnesium, tin, lead, zinc, and titanium, providing details on the sources, consumption and classification of scrap, and the technological trends and developments in recycling.

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There are a wide variety of furnace types and designs for melting aluminum. This article discusses the various types of furnaces, including gas reverberatory furnaces, crucible furnaces, and induction melting furnaces. It describes the classification of solid fluxes: cover fluxes, drossing fluxes, cleaning fluxes, and furnace wall cleaner fluxes. The article reviews the basic considerations in proper flux selection and fluxing practices. It explains the basic principles of degassing and discusses the degassing of wrought aluminum alloys. The article describes filtration in wrought aluminum production and in shape casting. It also reviews grain refinement in aluminum-silicon casting alloys, aluminum-silicon-copper casting alloys, aluminum-copper casting alloys, aluminum-zinc-magnesium casting alloys, and aluminum-magnesium casting alloys. The article concludes with a discussion on aluminum-silicon modification.