Magnesium Aluminum Alloy: The Ultimate FAQ Guide

Choosing a suitable magnesium aluminum alloy can be an overwhelming task.

A reason this guide will make the entire process easy and simple – it explores everything you need to know about magnesium alloy.

Which Elements Make Magnesium Aluminum Alloy?

Magnesium aluminum alloy rods

Magnesium aluminum alloy rods

Several elements within a magnesium aluminum alloy contribute to its relevant properties.

Besides, aluminum takes the bulk of the composition followed by magnesium.

The other elements come in small quantities but are vital for the stability of the magnesium aluminum alloy.

Also, you need to make these alloys using a high grade of aluminum material, normally at around 99.7% or even higher.

This will enable you to achieve the highest levels of reflectivity and corrosion resistance.

Here is the composition of all the elements that make up a magnesium aluminum alloy:

  • Magnesium [Mg] material ranges between 0.5% and 13% in composition
  • Boron [B] material occupies a value of up to 0.05%
  • Silicon [Si] will take up 2%
  • Nickel [Ni] will comprise up to 0.5%
  • Iron [Fe] takes up to 0.8%
  • Beryllium [Be] occupies up to 0.001%
  • Copper [Cu] take up to 0.2%
  • Zinc will occupy up to 3%
  • Lithium takes up to 3%
  • Chromium [Cr] will occupy up to 0.5%
  • Zirconium will represent up to 0.5%
  • Titanium will take up to 0.2%
  • Manganese will occupy up to 2%

Zirconium and iron within the magnesium aluminum alloy assist in increasing the temperature of recrystallization.

Adding silicon elements will enhance the fluidity of the alloy.

Incorporating chromium or manganese will rectify the corroding effect that you will experience due to the presence of iron.

Adding copper to the magnesium aluminum alloy lowers corrosion pitting by improving the overall corrosion.

Applying zinc will improve the strength and castability of the magnesium aluminum alloy.

However, the presence of zinc causes minimal to no impact on the corrosion.

The addition of titanium and boron elements will act as grain refiners to the magnesium aluminum alloy.

To lower the rate of oxidation of the magnesium element at high-temperature levels, you will add beryllium and even lithium.

This proves to be beneficial in a molten state.

Adding lead to this alloy will enhance machinability without losing its strength or its corrosion resistance.

Why Choose Magnesium Aluminum Alloy?

Some of the reasons as to why you should use magnesium aluminum alloy include the following:

Weight Saving

Using a magnesium aluminum alloy allows you to save an average of 60% in weight reduction.

This proves to be advantageous especially in marine and aviation vessels.

This means you can carry more load and lower the amount of power that you need during operation.

Weldability

The magnesium aluminum alloy has suitable weld ductility requiring no heat treatments after the welding process.

Corrosion Resistance

Magnesium aluminum alloy has a lower corrosion resistance thus suitable for use in varying environments.

For instance, it can withstand chemicals or moisture.

Besides, the tensile strength of this alloy can last for several years without much degradation.

Magnesium aluminum alloy part

Magnesium aluminum alloy part

Are There Limitations Of Magnesium Aluminum Alloy?

Besides having its limitations, this should not prevent you from using a magnesium aluminum alloy.

The cost of purchasing aluminum that you will use when making this alloy is high.

Can You Die Cast Magnesium Aluminum Alloy?

Yes, you can perform die casting on magnesium aluminum alloys.

This entails the use of both cold chamber and hot chamber die casting.

In hot chamber die casting, you will heat the magnesium aluminum alloy within the die casting machine.

Once the molten magnesium aluminum alloy achieves a molten state, you will use pistons to force it into a die.

Besides, hot chamber die casting is fast, lasting between 15 and 20 minutes.

However, in cold chamber die casting, you will heat the magnesium aluminum alloy in a separate location.

Afterward, you will transfer the molten magnesium aluminum alloy to the casting machine.

Here, you will force the molten magnesium aluminum alloy in a mold to form the desired shape.

The die casting machine will apply a pressurized plunger that will force the molten magnesium aluminum alloy within the mold cavity.

What Are The Characteristics Of Magnesium Aluminum Alloy?

Here are some of the properties you will find in magnesium aluminum alloys:

  • It has a melting point of about 600 °C or 1110 °F
  • The density of the alloy is about 1.9 g/cm3
  • It is not soluble in water
  • Also, it has an electrical resistivity of -7 10x Ω-m
  • The Poisson’s ratio stands at 0.29
  • It has a thermal conductivity of 125 W/m·K and a thermal expansion of 26 µm/m-K
  • The Vickers hardness stands at 88
  • Also, it has an ultimate tensile strength of 230 to 280 MPa

Where Can You Use Magnesium Aluminum Alloy?

Magnesium aluminum alloy finds its application in several areas.

These include the following:

  • Railings
  • Decorative trims
  • Window frames
  • Marine vessels
  • Structural sections
  • Profiles that you will cut to length
  • Wrought bar
  • Sheets
  • Dump truck bodies
  • Welding wires
  • Forgings
  • High strength foil
  • Tubes
  • Pressure vessels
  • Bars
  • Petrol tanks
  • Marine fittings and structures
  • Architectural parts
  • Automotive trims
  • Pressure cryogenic vessels

How Does Magnesium Aluminum Alloy Compare To Zinc Alloy?

Here is how these two compare:

Magnesium Aluminum Alloy

This alloy has the benefits of being lightweight, corrosion-resistant, and with suitable weldability.

Magnesium aluminum alloy has several elements that enhance its properties making it suitable for several applications.

Zinc Alloy

The main type of material you will use here is zinc.

This type of alloy has a low melting point meaning you need less pressure when performing casting.

Besides, it is one of the most castable alloys among all the popularly used alloys.

Also, since it has a low melting point, you can conduct hot chamber die casting, which is affordable.

Zinc alloy is also tough making it able to resist impact.

Also, you can use zinc alloy when casting delicate details and thin walls.

Zinc alloy allows for minimal trimming, machining, or finishing.

This is because the low pressure and melting points decrease the thermal shock that you might encounter when casting.

How Does Magnesium Aluminum Alloy Compare To Aluminum Alloy?

Aluminum alloy die cast part

Aluminum alloy die cast part

Magnesium aluminum alloy mainly comprises aluminum material in large quantities and magnesium.

Aluminum alloy is a material whose predominant metal is aluminum.

Besides, you can use several kinds of elements when making aluminum alloys such as copper, manganese, zinc, magnesium, etc.

Both of these offer suitable corrosion resistance, weldability, and are lightweight.

Is Magnesium Aluminum Alloy Strong?

Yes, the magnesium aluminum alloy forms a strong combination.

This is because of the addition of magnesium element, which enhances its strength yet retains the lightweight feature.

How Do You Test Quality Of Magnesium Aluminum Alloy?

Testing the quality of the magnesium aluminum alloy entails examining it to ensure it meets the manufacturing standards.

Some of the testing methods you can use include the following:

Destructive Testing

In this test, you will perform mechanical testing on the magnesium aluminum alloy and dispose of it afterward.

Thereafter, you will compare the test results with the manufacturing specifications.

Examples of destructive testing subtypes entail the following:

  1. Wear test
  2. Tensile test
  3. Hardness test
  4. Bend test
  5. Impact test
  6. Corrosion resistance test
  7. Fatigue test

Non-destructive Testing

This test examines the magnesium aluminum alloy without damaging it.

Examples of non-destructive testing subtypes include the following:

  1. Visual testing
  2. Leak testing
  3. Ultrasonic testing
  4. Radiographic testing
  5. Remote-field electromagnetic testing
  6. Eddy current testing
  7. Magnetic particle testing
  8. Dye penetrant testing

How Does Magnesium Aluminum Alloy Compare To Magnesium Alloy?

Magnesium die cast part

Magnesium alloy die cast part

Magnesium aluminum alloy entails aluminum as the main material.

However, the main material in magnesium alloy is magnesium.

Besides, you can still add other elements in magnesium alloy such as zinc, manganese, aluminum, silicon, copper, zirconium, etc.

The structure of the magnesium alloy appears as a hexagonal lattice thereby affecting the main properties of these alloys.

Besides, you can use both of these alloys in similar applications such as the automotive industry.

Which Surface Finishes Can You Apply On Magnesium Aluminum Alloys Parts And Components?

The surface finish you can apply on a magnesium aluminum alloy offers environmental protection and enhances the aesthetics.

Also, the surface finish can lower the roughness of the surface.

Some of the benefits of the surface finish entail the following:

  • Enhances durability
  • Improve electrical conductivity
  • Increases chemical resistance
  • High tarnish resistance
  • Enhance the appeal
  • High electrical resistance

Here are the types of surface finish you can apply on magnesium aluminum alloy parts and components:

Plating

This entails the use of chemical solutions to change or coat the surface of the magnesium aluminum alloy.

Plating can enhance the longevity, corrosion resistance, appearance, and surface friction of the magnesium aluminum alloy.

Brushing

This is a suitable method that assists in eliminating imperfections on the surface of magnesium aluminum alloys.

Brushing forms uniform grains that are parallel to the surfaces’ exterior.

In this process, you will use a wire brush or an abrasive belt.

Furthermore, wire brushing assists in removing slag from welding works, scale, and grit before you clean the alloy.

Buffing

This is a process you will perform on the magnesium aluminum alloy after machining to lower the surface roughness.

Besides, you can use lapping or honing with abrasive substances to enhance surface roughness by ribbing parts against each other.

Also, you can conduct polishing through manual or automatic procedures.

Since it minimizes surface roughness, it will enhance the luster of the magnesium aluminum alloy.

Grinding

This action takes place in grinding machines that contain abrasive wheels which smoothen the magnesium aluminum alloys.

Grinding machines come in different types that offer varying smoothing levels.

Besides, grinding will lower the roughness of the surfaces.

Some types of grinding machines include surface grinders, Blanchard grinders, centerless grinders, etc.

Hand grinders assist in eliminating slag or for cleaning.

Blasting

Here, you will use blasting machines such as sand-blasting machines to achieve a uniform texture matte.

In this process, you will force abrasive elements onto the magnesium aluminum alloy at high velocities.

Examples of these abrasive elements include metal pellets, sand, or steel shots.

The outcome is a clean, smooth, and soft magnesium aluminum alloy.

Also, you can conduct shot peening to convey compressive stress on the surface of the magnesium aluminum alloy.

This process will improve:

  1. Resistance to fatigue
  2. Resistance against corrosion cracking
  3. Fretting resistance, etc.

Vibratory Finish

This is a method of eliminating sprue, sharp edges and performing deburring on the magnesium aluminum alloy.

In this process, you will place the parts in a drum containing abrasive elements.

Thereafter, you will apply a tumbling vibratory action that will form a uniform yet random texture.

Besides, you can alter the speed and intensity of the vibration to cater to both large and small parts.

Coating

In this process, you will use oil-based paints and water to offer affordable protection against corrosion.

Besides, you can use unique paints able to withstand extreme environments i.e. marine applications.

Powder coating will apply a durable and decorative surface finish.

Heat Treatment

This is a process that will deliver suitable traits in the magnesium aluminum alloy once you achieve the final shape.

For example, you can harden parts via flame or inductive heating to enhance their wear resistance.

Hot Blackening

In this process, the machine will apply a layer of thin black oxide on the surface of the magnesium aluminum alloy.

This leads to the creation of a matte black finish that has a high resistance against abrasion.

Hot blackening entails inserting the magnesium aluminum alloy in tanks containing coolants, cleaners, and caustics.

This method is suitable for firearms, automotive components, and tools.

How Does Quantity Of Magnesium Affect Magnesium Aluminum Alloy?

Using high amounts of magnesium will increase the hardness value of the magnesium aluminum alloy.

Are There Different Grades Of Magnesium Aluminum Alloy?

Yes, the different grades include:

  • AZ31
  • AZ63
  • AZ81
  • AZ91E
  • AZ91D
  • AZ31B
  • AZ80
  • AZ61
  • AZ91
  • AM60
  • AZ92A
  • AZ92
  • AMCa602

For all your magnesium aluminum alloys, Inox offer perfect solution for you – contact us now.

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