Aluminum Die Cast Parts: The Ultimate FAQ Guide

I know you are probably looking for high-quality aluminum parts die-cast parts.

Or, you would like to learn more about aluminum parts.

Whichever the case, this guide explores everything you need to know about aluminum parts.

For more about die-casting aluminum die casting – read this guide.

Aluminum Die Casting Parts

It is the process of creating parts from aluminum metal through the die casting process.

Ingots of aluminum alloy are entirely molten due to very high temperatures heating effect.

A mold or liquid aluminum is injected into the cavity of the steel die under high pressure.

The cast aluminum parts are revealed by the separation of the solidified molten aluminum made up of two halves die.

Precisely formed resulting aluminum product is formed with a smooth surface and often requires minimal or no machining processes.

Using the same mold process can be repeated many times before it deteriorates given that steel dies are used.

For the high-volume production of aluminum parts aluminum die casting is ideal

An Aluminum Die Casting Machine

An Aluminum Die Casting Machine

What Are The Benefits Of Aluminum Die Casting Parts?

  • Production of very complex shapes that can be created effectively by neither extrusion nor machining is its most noteworthy ability.
  • Production of complex automotive parts is the perfect example, engine blocks, and transmissions.
  • Large and small parts are accommodated.
  • Have textured or smooth surfaces abilities.
  • Accommodates both large and small parts.

Are There Limitations Of Aluminum Doe Casting Parts?

  • The dies cost, machines and other equipment used are high.
  • Starting with small quantity production is not cheap.
  • For evacuation of air from the die cavity, there are special precautions necessary otherwise there will be entrapment of gases in form of porosity.
  • Getting a die casting prototype is impossible in the product development process.
  • High-fluidity metals are limited.
  • Economical alternative to other processes we need a large production volume.

Which Industries Use Aluminum Die Cast Parts?

Some of the most common industries:

i. Manufacturers of transmission machines.

ii. Manufacturers of oil pumps.

iii. Motorcycle industries.

iv. Engine internal combustion production.

v. Motor manufacturing industries.

vi. Manufacturers of automobile.

vii. Power construction industries.

viii. Decoration and architectural industries.

AN Aluminum Die cast part That is Used In Telcommunications Industry

An Aluminum Die Casting Part made For Telecommunications Industry

Which Techniques Do You Use In Aluminum Casting Parts?

Sand Casting

Especially with complex inner cavities making blanks with complex shapes is suitable with wide adaptability and low cost.

It is the only forming process for manufacturing cast iron parts or blanks with their poor plasticity properties.

Automobile engine cylinder blocks, craft shafts, cylinder heads, and other castings can use.

Steps In Sand Casting Process

For the mixing mix sand with a sand mixer and add appropriate clay.

Molds manufacturing for casting.

Into the sand, mixture put the mold and seal the box containing the sand mixture.

Select a suitable melting furnace to melt the metal after distributing according to the metal that is to be cast.

To the desired mold pour the liquid metal prepared in the previous step paying attention to safety.

Clean up the grit around the cast part after the liquid metal has cooled and solidified in the mold using a tool.

Sand Casting Process Underway

Sand Casting Process Underway

Investment Casting

Are suitable for industrial precision casting parts, they have high dimensional accuracy and geometric accuracy.

Surface roughness is high.

Cast alloy is not limited and can also cast complex casting.

Steps In Investment Casting Process

To make the mold choose a material that is easy to melt.

Cover the surface of the mold with several layers of refractory material to make the casting part’s shell.

To obtain a complete casting model Melt the cast iron mold again.

Fill with sand after high-temperature roasting and pour.

An Aluminum Part Made By Investment Casting

An Aluminum Mold Made By Investment Casting

Low-pressure Casting Process

For low-pressure casting to apply to various casting molds, casting multiple alloys to adjust liquid metal pouring speed and pressure.

To avoid getting involved in the gas filling without splashing molten metal process is smooth thus improving the qualification rate of castings.

The structure of the casting crystallizes under pressure is dense with a clear outline and smooth surface.

90% -98% increase in the casting process metal utilization rate.

Easy to realize mechanization and automation because of low labor intensity and simple equipment.

Steps In Low-Pressure Casting Process

At high temperatures melt metal into liquid.

To fill the liquid metal into the mold use pressure.

Under low-pressure liquid metal solidifies to form castings.

Process Of Centrifugal Casting

Used for axis-symmetric making parts such as hollow cylinders or disks.

The centrifugal casting process is of three parts namely Semi centrifugal casting process, true centrifugal casting process, and vertical centrifugal casting process.

Larger parts symmetrical on the vertical axis use semi centrifugal casting.

Flywheels and gear blanks etc. are products of centrifugal casting.

In the metal casting process, there is almost no metal consumption thus reducing waste and improving the process yield.

When producing hollow castings we do not need models but improve metal filling capacity for long casting tubular.
Mechanical properties of pores and slags increases with high density and almost no defects with casting.

To manufacture sleeve composite and barrel metal castings is convenient.

Steps In Centrifugal Casting Process Steps

Into a rotating mold pour molten metal.

To solidify and form under the action of centrifugal force fill the mold.

How A Centrifugal Casting Machine Works

 How A Centrifugal Casting Machine Works

Gravity Die Casting

Permanent mold casting is another name for gravity die-casting.

Metal casting’s heat capacity and thermal conductivity are large with a fast cooling rate.

Accuracy and lower surface roughness values ​​can be obtained when castings with higher dimensions thus good quality stability.

To reduce labor intensity, dust, and harmful gases to improve the environment never use gravel in the casting process.

Flow Process In Gravity Die Casting

Under the action of gravity with the metal, mold fills the liquid metal.

The liquid metal cools and solidifies in the casting model to form cast parts.

Lost Foam Casting

Lost Foam Coating

Lost Foam Casting

The complex manufacturing of metal parts and parts process is called lost foam casting.

Evaporated molten metal from the foam mold is kept still with sand during the lost foam casting process.

No sand core with high casting precision thus processing time reduced.

The high degree of freedom, design is flexible and there is no parting surface.

Production costs and investment reduced.

There is no pollution hence a clean production.

Steps In Lost Foam Casting Process

The wax or foam models are bonded and combined into a model of similar casting shapes and sizes.

Bury the refractory pain in dry quartz sand and vibrate the shape after brushing and drying.

To vaporize the model pour liquid metal under negative pressure.

After cooling and solidifying new casting method forms due to the model position that is occupied by the liquid metal.

Die Casting Vacuum Process

To exhaust gas from the mold cavity the process of vacuum die casting is used.

The cavity pressure rises with filled molten metal and is pressurized at high speed.

Exhaustion of gas reduction or elimination of the pores through a vacuum valve vacuum die casting is done inside the die casting.

The surface quality and mechanical properties of the die casting improve the plating performance.

Alloys with poor casting properties can use lower specific pressure to reduce the backpressure of the cavity.

To die-cast, larger castings are possible with a small machine.

Thinner castings can be die-casted and filling conditions are improved.

Die Casting Vacuum Process

The gas in the cavity of the die-casting mold is extracted in the die-casting process.

Eliminate or reduce pores and dissolve gases by advanced die-casting technology in die-casting parts.

The surface quality of die-cast parts and mechanical properties improves.

Illustration Of Die Casting Vaccum Process

How to Die Casting Vaccum Process Works

Squeezing Die Cast Process

The process of forming mixed-metal is called Squeezing die-cast.

Die casting combines with die forging.

Into a preheated, lubricated mold pour a specified amount of molten alloy and then under pressure forge and harden.

Internal defects such as shrinkage holes, pores, and shrinkage porosity can be eliminated.

High dimensional low surface roughness and accuracy.

Casting cracks can be prevented.

Automation and mechanization are realized easily.

Liquid metal’s high rate of utilization, stable quality and simplified process are energy-saving metals with potential application prospects forming technology.

-Die Casting Squeezing Process

Solidified liquid or semi-solid metal and flow-formed to directly obtain parts or blanks under high pressure.

What Determines Cost Of Aluminum Die Casting Parts?

The budget of the metal-forming process you choose determines the cost.

How many parts do you want and the purpose of your aluminum part to manufacture?

High volume and high complexity of parts is a very expensive design but it is worth it.

Which Defects Are Common In Aluminum Die Cast Parts?

Porosity Of Gas

Porosities of gas appear in oval, round smooth surfaces with bright white or yellow color in the body of die casting parts.

After machining the machined surface can be identified by visual inspection.

X-ray detection identifies the non-machined surface.

Soldering And Drags

With the die’s opening direction drags are parallel and appear as strip-shaped scratches with a certain depth on die casting parts surfaces.

The abnormal sticking of metal alloy and die cavity causes soldering.

The material in some areas of die casting parts surfaces causes soldering to appear.

The visual inspection identifies both defects.

Soldering In Aluminum Die Casts

Soldering In Aluminum Die-Cast


As different sizes of bulges on the surfaces of die casting parts blisters appear.

Underneath the surfaces gas expansion causes bulges.


On the surfaces of the die, casting cracks appear as linear or irregular patterns with the external force tendency of extension.

Defects can be identified by visual inspection, in cold crack material is not oxidized while in hot cracks material is oxidized.


The Die-casting part geometric shape does not match the drawing thus occurrence of overall and local deformation.

Visual inspection or gauge inspection identifies deformation.

Flow Marks

The flow of the metal liquid and the stripes are in the same direction on the surface of the die-casting part.

There are clearly different visible non-directional lines from the color of the casting base.

By visual inspection flow Marks can be identified with no tendency of strips and lines to extend.

Cold Flow

Irregular, obvious, and depressing linear lines are on the surface of die-casting parts.

The edges of the junction are smooth with narrow and small lines which if with external forces it may extend.

The visual inspection identifies a cold flow.

Turtle/Network Cracks

On the surface of the die-casting, there are net-like, hair-like protrusions or depressions.

There are continuous protrusions, depressions expand and extend with the increase of die-casting times.

The visual inspection identifies turtle cracks.


Depressions are on the thick-walled area’s surface of die casting parts.

The visual inspection identifies the defect.

Short Filling

The visual inspection identifies defects in missing some materials in a partial area of the casting surface.

Short Filling Defect

Short Filling Defect


There are thin and irregular-shaped metal sheets on the edge of the parting surface of the die-casting part.

The visual inspection identifies the flashes.


On the surface of die casting parts, sandwich-like layered defects are called interlayers which are usually seen on the parting line.

Visual inspection can identify the defect.

How Does Aluminum Die Casting Parts Compare To Zinc Die Casting Parts?

The electrical conductivity of aluminum is much more compared to zinc hence a better shield for RF/EMI.

As a heat sink, many manufacturers prefer aluminum.

In terms of weight, zinc has more weight about two and a half more than aluminum.

In a salty environment, aluminum decays faster than zinc.

Polishes of zinc are much better compared to aluminum.

Plated zinc parts are better than of aluminum.

How Do You Check Quality Of Aluminum Die Cast Parts?

i. Composition of Aluminum alloy analysis with a spectrometer.

ii. Using a metallographic analyzer analyzes the casting’s crystallization.

iii. With an X-ray flaw detector, detect the casting internal quality.

iv. Check with fluorescence analysis whether the casting surface has cracks on it.

v. Mechanical properties of castings are detected with a universal testing machine.

vi. Check the measurement sizes with calipers, for dimensional detection of castings three-coordinates and height rulers.

Which Alloys Are Suitable For Aluminum Die Casting Parts?

Some of the most common alloys are A360, A380, 383, B390, A413, and CC401.

Intended application when choosing an appropriate alloy is the primary consideration.

Excellent corrosion resistance is offered by A360, with very good fluidity, and pressure tightness when molten.

High hardness outstanding wear resistance while having the lowest ductility of all alloy cast is offered by B390.

For automotive engine blocks application, alloy A380 is the perfect jack-of-all-trades is alloy A380.

A combination of good casting and offering product properties is the most commonly specified alloy in a wide variety of casting products.

Is There Recommended Accuracy And Tolerance Of Aluminum Die Casting Parts?

It depends on the type of components you need.

However, aluminum die casting parts can attain tight tolerances.

How Can You Improve Quality Of Aluminum Die Casting Parts?

Sticky Mold

For the mold steel, the result of the adhesion of molten alloy is soldering on the die.

Mold sticking problems exacerbated due to high temperatures and corrosion are more common in special areas of the mold.

A barrier coating formation between molten metal and tool steel prevents sticking with more prone to stick alloys.

Lower temperature mold surfaces can be applied to silicone-free series release agents.


In the die casting process, the biggest problem is porosity.

To replace steel or iron parts die-casting processes are often used to make light parts from light metals.

Any situation that reduces the strength of components is avoided since the inherent strength of light metals is lower than that of steel components.

The cross-section of the casting small holes will have a large effect on its tensile strength.

Carbon/Cavitation Fouling

Only a thin film of the die-casting mold release agent is left after the moisture evaporates when the die-casting mold release agent is sprayed on the mold surface.

When the casting is released this film is usually removed.

The layer of lubricating film cannot be completely removed especially when the mold temperature is lower than the rated temperature.

In the mold cavity is where scaling can occur, reducing the amount of mold release agent is the best solution.

Each part of complex mold’s local temperature may vary greatly reducing the amount of die-casting release agent causing welding due to reduced fouling.

The above problems are alleviated while forming unified protection.

Water that dilutes the release agent is the main cause of scaling in the cavity.

To use demineralized water die-casting release demineralized agent is recommended.

After the water has evaporated the dissolved calcium and magnesium salts will precipitate if hard water is used.

The components tend to form deposits in the cavity since they cannot be decomposed by molten metal.

The chemical composition of the residue analysis in the cavity usually reveals the presence of a mold release agent component

Water that dilutes the release agent is the root cause of solid salts.

It can cause solids to settle in the mold cavity can be caused by the chaos of the water softening system.

Cold Partition

Traces of dark lines left by the path of molten metal sometimes shows at the casting of the surface.

For magnesium alloys and thin-walled cast sections, this is true.

Casting cannot even be filled completely in extreme cases.

On the surface of casting crack-like things appear with not fully fused marks left by the two layers of the metal surface when solidified.

When the filler is not full cold insulation condition indicates that the casting has started to solidify.

Too low melting temperature, too low mold temperature, or excessive cooling causes cold insulation.

Problems that may occur due to dissatisfaction with the casting filler are avoided effectively.

White Dot

To prevent adhesion between the casting and the mold surface is the main role of the release agent.

Adhesion of the coating or the coating may be affected by the use of a release agent.

White spot defects may occur if the release agent is not completely removed during the cleaning process.

What Should You Consider During Aluminum Die Casting Part Design?

Design a mold to separate and solidified the aluminum parts allowed to come out.

Consider a parting line in the early stage of die design because it marks where two halves of the mold come apart.

In cases when the molten solidify before reaching every die crevice, several injections points a die is designed.

When the mold is separated, surround the cavities with aluminum and still have the part come off.

We prefer walls with consistent thickness.

Which Surface Finishing Can You Apply On Aluminum Die Cast Parts?

Chem film- is a conversion finish electrically conducted thus no plating build-up.

Decorative finish- Are of different types of plating, painting, and bright finishing formulated for desired result achievement.


At the casting surface, an electrochemical process that converts aluminum into aluminum oxide is aluminum anodizing.

Aluminum dies casting natural corrosion resistance is improved.

Impregnation- the surfaces and subsurface are filled and sealed thus preventing porosity formation.

Chem Film Coating On aluminum

Chem Film Coating On Aluminum

What Is The Ideal Wall Thickness For Aluminum Die Cast Parts?

2mm is the preferred wall thickness for aluminum die-casting.

A lot of time customers look for lightweight castings which mostly depend on the thickness to weight ratio.

How Can You Eliminate Porosity During Aluminum Die Casting Parts Process?

Porosities are of two forms namely gas and shrink porosity.

Within the casting, air entrapment causes gas porosity.

Designers can see with mold flow where the air is likely to be trapped and design strategically placed vents tool for air elimination.

Modifying parts during design may allow the flow of material in an optimal flow pattern avoiding turbulence entrapping air pockets and features.

Thermal analysis is run with shrink porosity to isolate hot spots during solidification within a part.

A cooling channel in the die hot spots can be addressed to help in heat extraction.

Why Is Prototype Important Before Mass Production Of Aluminum Die Casting Parts?

From which all other products are made the first versions of a manufactured product are prototypes that contain the most important features.

For mass production, the same prototype material is used which contains the same features as the final product.

Creating an aluminum process die casting prototype is used during mass production.

Consistency during mass production is maintained.

The aluminum die-casting prototype specifications and characters are the same as the mass production parts.

From the request of hundreds of pieces, it helps you to save costs.

Aluminum dies casting prototypes can be launched to the market as small batch production.

The time that mass production would take will be saved.

How Does Aluminum Die Casting Parts Vs? Magnesium Die Casting Parts Compare?

Here are some critical aspects you should know:

Aluminum Die CastingMagnesium Die Casting
Are Cheaper than magnesium.Are expensive than aluminum.
Using cold chamber equipment, alloys are cast.Require hot chamber equipment.
Longer Casting cycles.Casting cycles is very short.
Under pressure, parts are more stable.Not so stable with poor tensile strength.
Aluminum Parts are Heavier.Magnesium Parts are lighter.
Achieving a thinner wall is impossible.It is possible to achieve thinner wall.
Corrosion resistance is excellent.Corrosion resistance is poor.

For all your aluminum die casting parts, contact Inox now.

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