Magnesium casting

Magnesium alloys benefit from grain refinement, which is carried out by inoculation with carbonaceous materials. This used to be done with hexachloroethane, but since 1 July 2003 this product is banned in Europe generally to ensure environmental protection and for health and safety reasons. This applies both for magnesium and aluminium alloys. 

---

Uses. Alkah metal and ammonium fluoroborates are used mainly for the high temperature fluxing action required by the metals processing industries (see Metal surface treatments Welding). The tendency toward BF dissociation at elevated temperatures inhibits oxidation in magnesium casting and aluminum alloy heat treatment. 

Table 4. Chemical Compositions and Physical Properties of Magnesium Cast and Wrought Alloys ...

Table 5. Mechanical Properties of Magnesium Casting Alloys ...

Heat Treating Sand and Permanent Mold Magnesium Castings, bull. no. 141—552, The Dow Chemical Co., Midland, Mich., 1987. 

In magnesium casting, sulfur dioxide is employed as an inert blanketing gas. Another foundry appHcation is as a rapid curing catalyst for furfuryl resins in cores. Surprisingly, in view of the many efforts to remove sulfur dioxide from flue gases, there are situations where sulfur dioxide is deHberately introduced. In power plants burning low sulfur coal and where particulate stack emissions are a problem, a controUed amount of sulfur dioxide injection improves particulate removal. 

Fig. 19.28 Distribution of galvanic effects around contact of a magnesium casting and a steel...

Aluminum Casting Copper and Alloy Casting Magnesium Casting Zinc Casting... 

Magnesium casting alloys, mechanical properties of, 15 358-359t Magnesium castings, heat treatment of, 15 357-358. See also Magnesium die castings... 

E 155 Reference Radiographs for Inspection of Aluminum and Magnesium Castings... 

Yttrium also finds application in titanium alloys where at concentrations of the order of 200 ppm it improves the ductility and ease of fabrication of vacuum arc-melted alloys. It is also used to improve the strength of magnesium castings and when used in combination with zirconium, as little as 100 ppm yttrium increases the conductivity of aluminium transmission lines by as much as 50%. 

Heat treatment -magnesium casting [MAGNESIUM AND MAGNESIUM ALLOYS] (Vol 15)... 

Calcium is also used in aluminum alloys and as an addition in a magnesium alloy used for etching, An alloy of 80% Ca-20% Mg is used to deoxidize magnesium castings. The metal also is used in the production of calcium pantothenate, a B-complex vitamin. 

The most extensive use of magnesium castings in automobiles commenced in 1936. with the inlroduciinu of the Volkswagen Beetle. Each Beetle used from 40 to 51) pounds (18 m 2.3 kg) of primary magnesium ingot plus scrap metal. 

TABLE 2. MAGNESIUM CASTING ALLOYS FOR AUTOMOTIVE APPLICATIONS... 

Table 4.67 Nominal composition, typical tensile properties and characteristics of selected magnesium casting alloys... 

Use Ceramics, concrete hardeners, waterproofing, mothproofing, laundry sour, magnesium casting. 

The existence of such defining rules would naturally suggest rule-based behavior, but other factors enter into the decision. For extreme indications, such as total absence of an indication or very high severity of indication, the decision will be trivial and essentially skill based. Thus, a missing component in an assembly will automatically trigger a rejection response, as will a major crack in a magnesium casting. In the former case, the implication is that... 

Thermal Expansion of Graphite Magnesium Castings Linear Thermal Expansion of Metals and Alloys Thermal Expansion of Ceramics... 

---