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Chapter 21. Magnesium. Magnesium Manufacturing • Magnesium Alloys • Magnesium Fabrication • Magnesium Properties. Precipitation-hardening magnesium alloys are indicated at the magnesium end of the phase diagram by a rapid decrease in magnesium solubility with a decrease in temperature.
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Chapter 21 Magnesium Magnesium Manufacturing • Magnesium Alloys • Magnesium Fabrication • Magnesium Properties
Precipitation-hardening magnesium alloys are indicated at the magnesium end of the phase diagram by a rapid decrease in magnesium solubility with a decrease in temperature.
Surface treatments are used to protect magnesium alloys in corrosive atmospheres.
The ASTM magnesium alloy and temper designation consists of four parts.
The quenching and artificial aging of AZ92A cause the compound gamma to precipitate as fine particles within the grains.
The microstructure of magnesium alloy ZH62A-T5 indicates the lamellar eutectic Mg-Th-Zn compound at the grain boundaries of a magnesium-rich solid solution.
The microstructure of sand-cast magnesium alloy EZ33A-T5 consists of a network of massive magnesium-rare earth compounds in a magnesium-rich solid solution.
The maximum forming temperature and time permitted for magnesium alloys varies with the composition of the alloy.
Welding filler metals for welding magnesium alloys have a wider freezing range than the base metals they join to provide good wettability and minimize base metal cracking.
Preheating is determined by the product section thickness and the degree of restraint in the joint.
Specific magnesium alloys are stress relieved after welding to avoid stress-corrosion cracking.
Compared with other metals, the strength-to-weight ratio of magnesium alloys is very favorable.