Magnesium AZ31B-H24 View AMS Numbers >
Magnesium AZ31B-H24 (AMS 4377)
Magnesium AZ31B-H24 is a partially annealed and partially strain hardened version of AZ31B, with the version “0” having only an annealed treatment and the H26 version fully hardened and partially annealed. This alloy is mainly used in applications that require lower weight and high strength. When compared to aluminum or steel alloys used in the same scenarios, Magnesium AZ31B-H24 provides much better strength to weight ratio. Parts made from this magnesium alloy are very stiff, which makes them a great choice for structural components.
Thanks to these properties, the H24 version of AZ31B is mainly used in the aircraft industry for manufacturing of fuselages, but it also finds use in other areas, such as smartphone and laptop cases, speaker cones and other parts in high-end audio gear, and RFI and EMI shielding in the computer industry thanks to its non-magnetic nature.
Magnesium AZ31B-H24 can also easily absorb vibration, which makes it a great choice for textile machinery and concrete tools. Car manufacturers have also started using AZ31B-H24 in supercars, specifically for manufacturing of stiff and lightweight components, such as racing car wheels.
This alloy is also characterized by very good strength and ductility at room temperature, outstanding thermal conductivity, high corrosion resistance, excellent weldability, and high recyclability. The material also supports manufacturing of very complex parts thanks to the exceptional dimensional stability.
With all that said, like all Magnesium alloys, AZ31B-H24 has one glaring disadvantage, and that’s flammability. This means that when working with one of these parts, special care must be applied by the worker to minimize the chance of fire, like the use of a magnesium fire arresting kit.
Magnesium is also irritating to the human body, especially to the eyes, and skin. The airway passages should also be protected because high doses of exposure to magnesium oxide fumes can lead to metal fume fever. Magnesium dust and fumes are most often created during machining, grinding, welding, or melting.
Tech Steel & Materials offers Magnesium AZ31B-H24 in one sub-type specifications and two shapes/forms:
- AMS 4377 (Plate and Sheet)
Chemical Composition of Magnesium AZ31B-H24
|Calcium, Ca||—||0.002 %|
|Manganese, Mn||0.20 %||0.40 %|
|Aluminum, Al||2.50 %||3.50 %|
|Silicon, Si||—||0.10 %|
|Copper, Cu||—||0.050 %|
|Iron, Fe||—||0.005 %|
|Nickel, Ni||—||0.005 %|
|Zinc, Zn||0.6 %||1.4 %|
*Not exclusively to the element mentioned, but that one predominates other elements that are used only in minimal quantities.
Fabrication and Working Instructions
Like all other magnesium alloys, AZ31B-H24 is easily machinable using proprietary lubricants specifically designed for the purpose. Parts can be formed at temperatures of 500° F (260° C), while high-strength welding can be achieved using metal arc and gas tungsten processes.
Mechanical and Physical Properties
|Density||0.0639 lb/in³||1.77 g/cc|
|Tensile Strength||42.1 ksi at room temperature
69.9 ksi at 599 °F, time 0.167 hour
89.9 ksi at 500 °F, time 1000 hour
131 ksi at 401 °F, time 1000 hours
210 ksi at 302 °F, time 0.167 hours
|290 MPa at room temperature
48 MPa at 315 °C, Time 601 sec
62 MPa at 260 °C, Time 3.6+6 sec
90 MPa at 205 °C, Time 3.6+6 sec
145 MPa at 150 °C, Time 601 sec
|Tensile Strength, Yield||31.9 ksi||220 MPa|
|Creep Strength||1.02 ksi||7.00 MPa|
|Ultimate Bearing Strength||71.8 ksi||495 MPa|
|Bearing Yield Strength||47.1 ksi||325 MPa|
|Shear Strength||23.2 ksi||160 MPa|
|Shear Modulus||2470 ksi||17.0 GPa|
|Modulus of Elasticity||2470 ksi at 599 °F
4350 ksi at 401 °F
|17.0 GPa at 315 °C
30.0 GPa at 205 °C
|Machinability (relative rating,
100 is the highest score)
|100 %||100 %|
Thermal Properties of Magnesium AZ31B-H24
|Heat of Fusion||146 BTU/lb||340 J/g|
|CTE, Linear||14.4 µin/in-°F at 32 – 212 °F
15.0 µin/in-°F at 68 – 392 °F
|26.0 µm/m-°C at 0 – 100 °C
27.0 µm/m-°C at 20 – 200 °C
|Thermal Conductivity||666 BTU-in/hr-ft²-°F||96.0 W/m-K|
|Melting Point||1120 – 1170 °F||605 – 630 °C|
|Solidus||1120 °F||605 °C|
|Liquidus||1170° F||630 °C|
Electrical Properties of Magnesium AZ31B-H24
|Electrical Conductivity – equal volume||18 % IACS|
|Electrical Conductivity – equal weight||95 % IACS|