Cast copper alloys physical properties

Table 3.18. Physical properties of selected cast copper alloys... 

Table 4. Physical Properties of Cast and Wrought Beryllium Copper Alloys...

The usual alloying additions to aluminum in order to improve physical properties include Cu, Si, Mg, Zn, and Mn. Of these, manganese may actually improve the corrosion resistance of wrought and cast alloys. One reason is that the compound MnAle forms and takes iron into solid solution. The compound (MnFe)Alg settles to the bottom of the melt, in this way reducing the harmful influence on corrosion of small quantities of alloyed iron present as an impurity [27]. No such incorporation occurs in the case of cobalt, copper, and nickel, so that manganese additions would not be expected to counteract the harmful effects of these elements on corrosion behavior. 

In addition to nickel alloys, nickel also forms an important alloying element in stainless steels and in cast irons, in both of which it confers additional corrosion resistance and improved mechanical and engineering properties, and in Fe-Ni alloys for obtaining controlled physical and magnetic properties (see Chapter 3). With non-ferrous metals nickel also forms important types of alloys, especially with copper, i.e. cupro-nickels and nickel silvers these are dealt with in Section 4.2. 

The metal casting industry conventionally divides casting products into ferrous and nonferrous metals, in particular, iron-based, steel-based, aluminum-based, and copper-based castings. The other castings of low fractions include magnesium, lead, zinc, and their alloys. In the U.S., the foundry industry currently produces 11 million tons of metal product per year, with a shipment value of 19 billion. Of them, iron and steel accounted for 84% of metals cast.5 The remaining 15% of foundry operations are concerned with aluminum, copper, zinc, and lead production. Table 4.2 summarizes critical physical and thermal properties of aluminum, iron/steel, and cast iron. 

The properties of aluminum alloys (mechanical, physical, and chemical) depend on alloy composition and microstructure as determined by casting conditions and thermomechanical processing. While certain metals alloy with Al rather readily [9], comparatively few have sufficient solubility to serve as major alloying elements. Of the commonly used alloying elements, magnesium, zinc, copper, and silicon have significant solubility, while a number of additional elements (with less that 1% total solubility) are also used to confer important improvements to alloy properties. Such elements include manganese, chromium, zirconium, titanium, and scandium [2,10]. 

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