Cored metal casting

The basic fusible-core technique, a take-off of cored metal casting, makes it possible to produce simple to very complex hollow structural products. It involves using a fusible core inside the plastic part or structure. This core permits forming the desired plastic shape. The core material is a type that will not collapse or change shape during a pressure-temperature-time processing cycle. Shape is not usually the problem, since the core material is restricted. 

Metal-casting cores/molds, furfuryl alcohol resins in, 12 272-273 Metal catalysis, dye degradation by, 9 381-384... 

Subsequent addition of H2S or Na2S causes the precipitation of the off-cast core ions back onto the particles. The ion replacement process, requiring the sacrifice of the newly re-deposited core metal ions, can then be repeated in order to increase the thickness of the well layer. This process has been successfully repeated for up to three layers of well material. The well is then capped with a re-deposited layer of core metal ions to generate the Ml QD/QW structure. The thickness of the cladding layer could be increased by addition in several steps (up to 5) of the metal and sulfur precursors. ... 

Cavityless metal casting, also known as full mold or foam vaporization,was developed in 1956, The process allows you to produce complex shapes,including undercuts and hoilows,without the bother of draft angles,multi-piece molds,suspended core sections, etc. 

The use of polyurethane as a binder has found two interesting applications foundry cores and woodchip particleboard. The foundry industry has recognized the value of polyurethane adhesive binders to bind sand foundry cores for metal casting. This application is increasing steadily. The use of isocyanate binders for woodchip particleboard is receiving significant attention. The... 

Conventional water based or alcohol based core washes can be used to treat the surface of the cores. This type of treatment is in some cases to improve the surface of the metal casting or the hardness and shelf life of the core. Shelf life is the period of time after making for which the sand core is useful. 

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