Magnesium Alloy: The Ultimate FAQ Guide

Magnesium alloy refers to mixtures of magnesium with different metals.

The common metal used in creating this alloy includes aluminum, copper, zinc, silicon, manganese, zirconium, and rare earths among others.

Generally, magnesium alloys are known for various favorable structural properties, making them suitable for different projects and applications.

In this article, we will look at various elements surrounding magnesium alloy.

Take a look:

What Are The Main Types Of Magnesium Alloys?

Technically, magnesium alloys are often categorized into two; cast alloys and wrought alloys;

Magnesium alloy

Cast Magnesium Alloys

These are primarily the type of magnesium formed by pouring molten liquid metal into a mold where it solidifies to the desired shape.

Most cast magnesium alloys consist of numerous amounts but hardly exceed 10% of manganese, aluminum, and zinc as primary alloying elements.

However, other alloying elements like zirconium are usually incorporated, especially to improve creep resistance.

Moreover, mechanical properties of cast magnesium alloys are often augmented by heat treatments.

Wrought Magnesium Alloys

These refer to the type of magnesium subjected to various mechanical workings such as extrusion, forging, and rolling operations to attain required shape.

Nonetheless, manganese, zinc, and aluminum are the main alloying elements of wrought magnesium alloy.

This category of magnesium alloy are often sorted into heat treatable and non-heat-treatable alloys.

Ordinarily, wrought magnesium alloys have a smaller compressive proof strength than tensile proof strength.

Besides, they exhibit stringy texture in the deformation direction, enhancing the tensile strength.

Nevertheless, here are the common magnesium alloys you will usually find in different applications across various sectors;

AE44

It mainly consists of 92% and 4% magnesium and aluminum metal, respectively.

Also, this magnesium alloy consists of 4% mischmetal, which is an alloy of rare earth metals but also contains traces of cerium and lanthanum.

AE44 also allows attractive high mechanical properties, temperature, good corrosion resistance and die castability, and generally durability.

Majorly, this particular magnesium alloy is commonly used in automotive industry, specifically for structural components operating at high temperatures.

AJ62A

It is a die-castable magnesium alloy containing about 91.8% of magnesium, 6.6% of aluminum, 0.2% zinc, 0.08 silicon, and 0.5% manganese.

AJ62A exhibits better creep resistance at high temperatures and excellent corrosion resistance.

This alloy is majorly used in automotive applications where good creep and high-temperature properties are a concern.

Specifically, AJ62A has been used for making hybrid engine blocks in high-performance vehicles.

WE43

This magnesium alloy is made of about 4.3% Yttrium, 7.1% aluminum, 0.4% Zirconium, 4.4% rare earths, and the rest is magnesium.

It exhibits a metric density of 1.8 g/cm³ and a melting point of 540-640°C.

WE43 also has a tensile strength of 250 Mpa and thermal conductivity of 51.3 W/mK.

It is often used in different applications for making various components such as aero engines, sports cars, power systems, missiles, helicopter transmissions, etc.

AZ31B

It is a wrought magnesium alloy exhibiting reasonable strength, room temperature, ductility, weldability, and corrosion resistance.

AZ31B contains 96% magnesium, about 3.5% aluminum, 1.3% zinc, 0.2% manganese.

This alloy finds its applications in several uses, such as aircraft fuselages, concrete tools, laptop cases, and speaker cones.

It can be superformed at relatively elevated temperatures to produce various complex parts for automotive uses.

AZ91

AZ91 contains a large fraction of intermetallic compounds of the β-Mg₁₇Al₁₂ phase.

However, other than magnesium, which forms about 90.8% of this alloy, it also contains 8.25% aluminum, 0.63%, 0.0035%, and 0.22% zinc, silicon, and manganese, respectively.

It exhibits relatively high strength, good castability, and excellent corrosion resistance.

Mostly, AZ91 is used in a wide range of die casting applications.

Magnesium alloys

Why Is Using Magnesium Alloy Beneficial To Your Applications?

For the longest time, magnesium alloys have been fundamental in different applications due to their outstanding properties.

In essence, these alloys are beneficial in their respective applications in several ways.

Some beneficial reasons why you ought to consider magnesium alloy for your projects include the following;

Lightweight

Ordinarily, the components of magnesium alloys are 76% and 34% lighter than steel and aluminum, respectively.

In essence, this material compares favorably with many injection molding thermoplastic materials regarding weight.

As such, they increase efficiency, performance, and reliability in different applications

High Versatility

You can easily use magnesium alloys to make a wide range of parts or components for various applications.

Of course, this is fundamental since it increases convenience.

Eco-friendly

All magnesium alloy components are 100% recyclable.

Besides, it has constant supply and availability since magnesium is among the leading abundant elements in the world.

Essentially, this is beneficial since it means you can get it affordably, and its availability is guaranteed.

Thin Wall

Often, the nominal wall thickness used for molding most magnesium alloy parts can be up to 0.5mm.

Ideally, this thin wall provides high-strength accurate moldings.

Even so, combining the versatility of this process and tooling capabilities injection molding with incredible material flow.

Thus, magnesium alloy opens new complex, space-efficient design possibilities in numerous applications.

High Strength And Vibration Absorption

Typical magnesium alloys have a great tensile strength of about 20 times stiffer than ordinary engineering thermoplastics.

Besides, it exhibits high vibration absorption making it the ideal option for most applications where shaking is a concern.

Cost-effective

Essentially, the fact that magnesium alloy is versatile and readily available makes it quite affordable.

Moreover, the global supply for this material is increasing, which guarantees high-volume consistency leading to lower costs.

How Does Magnesium Alloy Compare With Aluminum Alloy?

Ideally, aluminum and magnesium alloys are the most commonly used ones in various industries.

They present different structural and chemical compounds, which makes them relatively apart.

Here are some ways these two types of metal alloys compare;

Aluminum Alloy

It is arguably the most common alloy used in die casting industry.

Structurally, aluminum alloy is lightweight, exhibits high ductility and malleability making it easy for precision machining.

The main aluminum alloying elements include copper, zinc, silicon, manganese, and magnesium.

It is quite strong, about a third of steel’s density hence giving it a formidable strength t- weight ratio.

Moreover, aluminum alloy is a great anti-corrosive, which is vital in giving your casted parts better durability.

The melting point of aluminum alloy is relatively high, making it sturdier, especially at higher temperatures.

Essentially, the higher the aluminum levels in an alloy, the riskier it is in terms of cracking or shrinkage.

Magnesium Alloys

Ordinarily, the biggest asset of magnesium alloy is its lightweight property making it the most preferred metal for casting processes.

Moreover, you can combine it with a few elements, such as aluminum, to form a lighter alloy.

Magnesium alloys have a lower melting point than aluminum alloys.

Besides, these alloys have a hexagonal lattice structure that usually affects their fundamental properties.

Typically, it is difficult to perform cold working on magnesium alloy since they have a complicated hexagonal lattice than in aluminum.

However, these alloys exhibit good resistance to corrosion and are also quite durable.

In essence, aluminum and magnesium alloys have a few differences, but you can still attain best results when you use them in various applications.

But the ultimate choice of the specific metal alloy to go for between these two depend on the exact demands of the application.

Is Magnesium Alloy Toxic?

Ideally, magnesium alloys contain different alloying elements.

Some of these elements contain different impurities that must be controlled properly.

In a finely divided form, magnesium alloys can be relatively toxic and highly explosive.

How Do You Select The Best Magnesium Alloy For Your Application?

Die cast magnesium part

Ordinarily, magnesium alloys are versatile, and you can find them in a wide range of variations.

But in many instances, it is imperative to look into various factors to find the most appropriate one for your application demands.

Some of the factors you may look at include the following;

Alloying Material Composition

Often, the available magnesium alloys are distinguished primarily by the specific alloying materials.

The essence here is every alloying material plays a specific role in establishing the particular magnesium alloy.

Specific Application Demands

Notably, different applications that use magnesium alloys have various demands depending on the application specifications.

It is imperative to look into the application’s needs to enable you to determine the right magnesium alloy, which fits it.

Price

The cost of magnesium alloys often varies based on many factors.

Thus, it is necessary to find one that fits within your budget and suits your particular application requirements.

Forming Method

Generally, magnesium alloys are available in either cast or wrought alloys.

Cast is formed by solidifying molten metal to a particular required shape.

On the other hand, wrought alloy is made through various mechanical operations such as rolling, forging, and extrusion among others.

Thus, the most suitable type will depend highly on the specific mode of formation that suits your application.

How Do Magnesium Alloy And Steel Alloy Compare?

Magnesium alloys and steel alloys draw quite a lot of comparisons in various structural, mechanical and chemical aspects.

Some of these comparisons include the following;

• Magnesium alloy is relatively lightweight, almost 75% lighter than steel alloys. Of course, this makes the former an ideal choice, especially for most applications where weight is a concern, such as in aero engines and sports cars.
• It is comparatively easy to attain complicated thin-walled near net shape casting with magnesium alloy than steel alloy.
• You can easily consolidate individual components into single die-cast magnesium to enhance rigidity and reduce welding costs. On the other hand, this is quite difficult to achieve with most steel alloys.
• Magnesium alloys reduce tooling costs significantly since you can easily consolidate numerous parts into a single part, unlike steel alloys.
• Magnesium alloys exhibit superior dimensional stability and repeatability to steel alloys.

What Machining Techniques Can You Use On Magnesium Alloy?

Technically, magnesium alloys have ideal machining ability features, making it easy to use various machining operations on them.

Simply put, you can fabricate magnesium alloy using a wide range of machining operations such as the following;

Magnesium alloy parts in automotive industry

Punching

This is a machining process, which entails removal of scrap plug slug from a metal workpiece every moment the punch enters the punching die.

Ideally, punching is often used for creating holes on the surface material of a workpiece, thus an economical way to machine magnesium alloy.

Milling

It refers to a cutting process, which uses a milling cutter to remove unwanted material from a workpiece.

This process removes the unwanted materials by carrying out various separate, small cuts.

Drilling

This machining operation involves cutting a workpiece using a drill bit to create a circular cross-section hole.

The size of the hole you create on the workpiece is dependent on the specific drill bit size you are using.

Sawing

It is a process, which uses a saw blade to cut a large metal workpiece into relatively smaller pieces.

Ideally, this is one of the best methods for cutting different magnesium alloys into size.

Turning

This is a machining process, which involves removal of unwanted materials from a workpiece to create rotational parts.

What Is The Service Lifespan Of Magnesium Alloy Parts?

Generally, most structural properties of magnesium alloy parts indicate that they are relatively durable.

They are strong and resistant to numerous weather and mechanical conditions, making them quite durable under normal circumstances.

However, the actual durability of most magnesium alloy parts is usually dependent on numerous factors, such as the precise applications.

If the application involves relative mechanical aggression, these parts can only withstand such conditions up to specific extents.

Secondly, the chemical composition of the specific magnesium alloy the part is made of also determines the longevity.

Some alloying elements are usually incorporated to enhance strength and overall resistance of magnesium to increase durability.

In a nutshell, magnesium alloy parts are generally durable, but the actual durability depends on the specific application conditions.

Is Magnesium Alloy Expensive?

It is relatively costly, almost twice more than aluminum alloy.

However, the actual cost of the element depends on various factors, such as the alloying composition.

Some types of magnesium alloys are more expensive than others depending on the specific composition of the alloying metals.

Also, the cost varies based on the particular manufacturer you are purchasing from.

Ordinarily, different companies always price these materials differently based on several factors regarding production and brand position.

Therefore, there is no definite price for magnesium alloy.

What Are The Ideal Surface Coating Techniques For Magnesium Alloy?

There is plenty of surface coating options you can use to protect the material surface of magnesium alloys.

Ordinarily, the common options often used include the following;

Electroplating – It is a technique of depositing a metal coating on surface of magnesium alloy by applying a negative charge and immersing it in a chemical solution.

Chemical plating – This process creates a metal coating on surface of magnesium alloy by autocatalytic chemical reduction in a liquid bath.

Anodizing – It refers to an electrolytic passivation process used for increasing thickness of natural oxide on surface material.

Powder coating – It involves applying a free-flowing dry powder on surface material of magnesium alloy.

Plasma electrolytic oxidation – This surface coating method involves generating oxide coating on surface of magnesium alloy.

Vacuum deposition – It produces thin films on the surface material that guarantees high quality and high performance.

Thermal spray painting – This coating technique involves spraying melted compounds onto the surface of magnesium alloy material.

Is There Size Limitation For Magnesium Alloy?

Not really.

The forming processes of magnesium alloys allow you to get the material in different sizes.

Of course, this is important because it makes it possible for you to attain the right size, which meets the needs of your application.

Which Quality Standard Certifications Do Magnesium Alloy Comply With?

Most quality standards certifications for this material often vary from one country to another.

In essence, different countries and economic regions usually have specific stipulated quality certifications these alloys needs to comply with.

However, the common quality standard certifications that most magnesium alloy parts comply with include the following;

• American National Standards Institute (ANSI)
• American Standards for Testing and Materials (ASTM International)
• Underwriters Laboratory (UL)
• CE certification
• International Standards Organization (ISO)
• Restriction of Hazardous Substances Directive (RoHS)

What Is The Strongest Magnesium Alloy?

Super magnesium alloy

This magnesium alloy is formed with magnesium and rare earth elements.

Super magnesium alloy features 50% lighter than titanium and 56% stronger than grade one titanium.

Besides, it is 21% stronger than 6061 aluminum and 75% lighter than steel.

If you have any questions or inquiry about magnesium alloys, contact us now.