Newton's metal

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Newton's metal is a fusible alloy with a low melting point. Its composition by weight is 8 parts bismuth, 5 parts lead and 3 parts tin; its melting point is 97 °C.

Newton's metal is comparable to Cerrobend, but avoids its toxic cadmium content. This has encouraged its use for medical applications for easily shaped shielding during radiotherapy. [1]

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Pot metal is an alloy of low-melting point metals that manufacturers use to make fast, inexpensive castings. The term "pot metal" came about due to the practice at automobile factories in the early 20th century of gathering up non-ferrous metal scraps from the manufacturing processes and melting them in one pot to form into cast products. A small amount of iron usually made it into the castings, but too much iron raised the melting point, so it was minimized.

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Fusible plug

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Berlin Foundry Cup kylix

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Soldering process of joining metal pieces with heated filler metal

Soldering is a process in which two or more items are joined together by melting and putting a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Unlike welding, soldering does not involve melting the work pieces. In brazing, the work piece metal also does not melt, but the filler metal is one that melts at a higher temperature than in soldering. In the past, nearly all solders contained lead, but environmental and health concerns have increasingly dictated use of lead-free alloys for electronics and plumbing purposes.

Selective laser melting 3D printing technique

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Bismuth–indium

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References

  1. "Newton's metal as a new home-made shielding material". Radiation Effects and Defects in Solids . Taylor & Francis. 162 (1): 53–57. January 2007. Bibcode:2007REDS..162...53K. doi:10.1080/10420150601045382.