ABS Injection Molding

Inox ABS Injection Molding

Inox has the expertise and team to help you with abs injection molding needs. Choosing abs injection molding from Inox provides great benefits to your applications.

Inox abs injection molding has excellent machinability and easy to mold. It has dimensional stability, high impact strength,  high stability under load, and high tensile strength and stiffness.

Our abs injection molding is easy to use in the injection molding process considering that it has a low melting temperature and can maintain its performance and characteristics in extreme temperatures. Plus, it can be attached with other polymers, which is easy to glue, paint, and color.

Inox is your preferred go-to source for precision quality ABS injection molding services. ABS materials are well known for their moderate heat performance, good machinability, and versatility that makes them popular for a wide range of industries.

Whether you need abs injection molding for industrial applications or medical devices and sports equipment, InoxCast has a lot to offer: injection molding, medical molding, overmolding, insert molding, ultrasonic bonding, and micro molding.

Inox ABS Injection Molding Advantages:

• Very good resistance to most acids, oils, and alkalis
• Good machinability
• High stability under load
• Very good dimensional stability
• Good heat resistance
• Excellent ductility
• Creep resistant
• Recyclable

Inox will be your best partner for your abs injection molding needs. We will always provide reliable, outstanding,  and quality work.

Reach out to our team right away!

ABS Injection Molding: The Ultimate Guide

In this guide, you will find all information you are looking for about ABS injection molding.

Whether you want to learn about ABS material grade, benefits, injection molding process, or applications – you will find all information right here.

So, keep reading to learn more.

1.  What Is ABS Injection Molding?

ABS is an acronym for Acrylonitrile Butadiene Styrene which is a thermoplastic that is amorphous, opaque and resistant to impact.

ABS Injection Molding involves heating of the ABS Resin and directly injecting it into custom-made mold.

This is done under high pressure for the mold cavity to be filled and the solid part formed.

The ABS Resin is then allowed to cool while keeping its new shape and the mold is later opened and the part ejected.

ABS Injection molding

2.  How Viscosity Affect ABS Injection Molding

Viscosity can be simply described as the measure of a fluid’s ability to resist flow.

The melt temperature of ABS pellets is a very important processing consideration and is directly related to the Viscosity of the ABS.

In the event that the ABS pellets are heated and melt beyond the temperature they plasticize, the material becomes hard to old due to increased viscosity.

This characteristic is very different when compared to other molding amorphous plastics.

In amorphous plastics, there is a decrease in viscosity when the temperatures go beyond the plasticization temperature.

Viscosity will also decrease when the processing temperature becomes exceeded.

Plastic injection molding process

3.  Which Properties Of ABS Makes It Suitable For Injection Molding?

Acrylonitrile Butadiene Styrene (ABS) is an amorphous thermoplastic having an equally low melting point when being injection molded.

Its melting point is slightly above 100°C while its injection typically takes place at temperatures slightly above 200°C.

Its properties exhibit a good correlation between its constituent components as follows:

• Its resilience and ductility is provided by butadiene
• Its strength is enhanced by the nitrile bonds
• It gets its aesthetic finishing from the styrene components.

ABS properties making it ideal for Injection Molding include:

Low Cost: ABS material is readily available in abundance with low energy requirements for its molding process.

Both of these factors significantly reduce its cost of production.

Chemical Composition: the ABS chemical components ensure optimally receptive for post processes involving other chemicals.

Such processes may include painting and gluing.

Low Melting Temperature: ABS has very low energy requirements when it comes to melting it.

It also uses a very low molding temperature meaning production speeds are very high compared to other injection molded plastics.

Surface Finish: when the appropriate processes are applied, ABS achieves impeccable surface finishing.

This makes it the most suitable for end user products used commercially.

Recyclability: ABS being an amorphous thermoplastic, it can easily be recycled by melting it down and using it for other applications.

Machinability: ABS can easily undergo mechanical post processing procedures due to its favorable mechanical properties.

Transparency: ABS parts can be conveniently used in applications requiring see-through parts due to its natural transparency.

It also makes addition of different colors to the final part very easy.

Impact Strength: due to the elasticity of the ABS material, the products produced using it exhibit excellent impact strength.

4.  What Are The Applications of ABS Injection Molding?

Plastic materials made using ABS Injection Molding are commonly used in our day to day activities.

Due to their resistance to several chemical and physical changes, these plastics are usually very useful in both commercial and industrial applications.

Its applications in the various areas include:

Molded ABS Parts

Electrical Industry: uses of Injection Molded ABS parts in the electrical industry set up include computer keyboards and electronic enclosures.

Commercial Applications: the commercial industry employs the ABS Injection Molding technique to manufacture many products used in homes.

These products include food processors, refrigerator liners, control panels and vacuum cleaners.

Building and Construction Industry: pipes and other fittings used in the construction industry are usually made from Injection Molded ABS plastic.

This is because it can withstand physical and chemical changes and it has a very good impact resistance.

Automotive Industry: most automotive parts that aim at reduction of weight are being made from ABS Injection Molded parts to replace metals.

Such parts include pillar trims, components of the dashboard, door loners and handles and seat belt parts.

Leisure Equipment: they include equipment used in sports such as parts of tennis racquets, various musical and entertainment equipment.

Medical Industry: they include medical equipment such as compressors and nebulizers.

5.  Why Dry ABS Before Injection Molding?

ABS plastics have the characteristic of absorbing water anytime they are used in any form of processing material.

This means that it is very crucial for the ABS plastic material to be thoroughly dried before any processing is carried out.

The characteristic of absorbing moisture normally results in in very many problems in design and performance.

The major problems are an increase in the operating costs and a significant amount of time spent in processing it.

Furthermore, if the water is not taken off the ABS plastic, then the injection molded parts will tend to be cloudy.

Absorption of water may also occur when the heat-resistant ABS resin has been stored or is being transported.

The moisture absorption range during storage or in transit is usually within 0.2% to 0.4%.

However, the moisture content of the ABS plastic molding has to be drastically reduced to 0.05% or less before processing begins.

This goes a long way in preventing any defects that will arise from the ABS Injection Molding during its processing.

Drying takes place at temperatures ranging between 80°C to 95°C with a completion time of about three to four hours.

6.  How Does The Holding Pressure Affect The Quality Of ABS Injection Molding?

The quality of any ABS Injection Molded plastic is greatly influenced by the molding time taken and a reasonable holding pressure.

The density of the molded ABS part is increased when the holding pressure is very high.

This results in reduced part shrinkage with a very refined surface quality although the part strength is endangered due to the creation of a big internal strength.

This appropriate solution is to use a holding pressure that is low provided the surface requirements are fulfilled.

The molds dwell time is set centered on the time required for the ABS Injection Mold gate to be sealed, after it is solidified.

The screw advancing during this process does not apply any pressure on the ABS plastic part.

When the holding time becomes too long, the internal stress in the mold becomes very large.

When the dwell time is too little, then the ABS plastic part can easily experience shrink problems and its measurements become unstable.

7.  Is ABS Injection Molding Safe?

ABS Injection Molding can be classified as non-toxic because the ABS resin used is a harmless thermoplastic.

There has been no officially reported case of adverse health concerns resulting from ABS plastic exposure.

It is a stable compound containing no form carcinogens, is stable with no incidences of leaching.

This makes it a totally safe form of plastic for manufacturing toys for kids and making other important industrial and home use products.

However, ABS Injection Molded parts are not advisable for use as medical implants.

This is because of a variety of limitations based on their physical attributes to act as replacement natural parts but with no chemical significance.

The ABS plastic can easily be recycled by melting it and using it in other applications since it is largely biocompatible.

This makes it easy to blend it with other industrial materials in the production of various high quality commercial products.

8.  What Are The Advantages Of ABS Injection Molding?

There are several benefits that can be found in ABS Injection Molding that various industries find very important in operations.

Some of these advantages include:

Energy Efficiency

The machines used in ABS Injection Molding provide outstanding performance when it comes to these thermoplastic processing.

An efficiently repeatable and continuous production performance is guaranteed with their strength and dynamics.

Accurate Reproducibility

Complex parts used in complex applications can be produced by the ABS Injection Molding Process.

Most of the other injection molding processes are limited to producing simple parts used in normal applications.

The ability to incorporate complementary techniques while regulating the injection molding enhances accuracy.

It also ensures that the shape of the parts is reproducible with very high quality molded parts.

Variety of Applications

Versatile applications can be achieved when using the ABS Injection Molding process.

The injection process is conditioned to work with various sizes of ABS resins achieving brilliant integration capabilities.

Additive Qualities

An addition of fibers on the ABS Resin (normally fiberglass) increases the strength of the molded part.

Additives usually assist in preventing aging aspects such as sunlight and antioxidants while other additives enhance heat resistance.

Heat Morphic

When ABS plastic is molded at extremely high temperatures, a very high gloss is produced with good heat resistance.

On the contrary, ABS Injection molding carried out at lower temperatures improves its load strength and impact resistance.

Precision

ABS Injection Molded Parts are appropriate for design applications that require very high tolerances.

When properly designed, design accuracies that are within ±.001 inches can be achieved.

Such measurements can be easily repeated on other production runs using different equipment.

Multiple Finishes

Most ABS Injection Molded Parts contain a very smooth surface finish after production that is similar to the required final look.

However, not all applications require a smooth surface finished part depending on application conditions.

Color Control

ABS Injection Molded parts can have colors ranging from clear to any color that a client requires.

This is made possible by aligning the ABS resin with additives and using biocompatibility to get the needed coloration.

Flexibility

Flexibility is a major requirement when it comes to injection molded parts and ABS achieves that after part processing.

This gives a lot of freedom when it comes to choice of design especially in comparison to metals and other stiffer plastics.

ABC injection molding process

9.  What Are Limitations Of ABS Injection Molding?

While ABS Injection Molding has many operational advantages, it has its fair share of downsides. Some of these disadvantages include:

Poor UV Resistance

Injection Molded parts made of ABS plastics tend to not fare well when exposed to sunlight.

The ABS plastic material has the tendency of degrading when continuously exposed to the ultraviolet rays found in the sunlight.

To prevent this, surface finishing has to be applied on all the ABS Injection Molded parts.

They are normally coated with a material that is UV-resistant to provide it with sufficient protection.

Poor Fatigue Resistance

ABS Injection Molded plastic parts have a very poor fatigue resistance hence they are not suitable for high stress applications.

When continuously exposed to stress or strain, they become easily degraded.

High Smoke Evolution

In as much as the ABS plastic material is classified as non-toxic to human beings, it produces a lot of smoke during fabrication.

This may pose a health hazard to the technicians and fabrication operators.

10.  What Are The Factors Affecting The Surface Finish In ABS Injection Molding?

Using dedicated finishes when treating ABS Injection Molded parts is the perfect way to have maximum control over the part texture.

However, some factors can easily manipulate the parts surface finish before and during its processing.

Such factors include:

Material Choice

There is a wide variety of materials that can be used in surface finishing of ABS Injection Molded Parts.

However, not all the materials can react effectively with the ABS plastic to achieve the desired surface finish.

ABS plastic can easily achieve a smooth textured surface finish as compared to roughening it up. Certain additives like colors and fillers can also affect the surface finish of the ABS part

Functional Reasons

Functional aspects also play a determinant role in the part surface finish as compared to aesthetic reason.

If an ABS Injection Molded part requires to be painted post-processing, then a textured finish guarantees the paint sticks.

Tooling

The surface finishing of the ABS Injection Molded part is also greatly influenced by the mold itself.

There are various metals that can be used to manufacture molds but Aluminum and Steel are the most preferred.

Smooth finishes are easily attained when the molds used are manufactured from hardened tool steel.

A steel mold ensures surface roughness is minimal thus is preferred when aesthetic finishing is a priority.

Process Variables

Process variables such as temperature and speed of injection greatly impact the surface finish of the ABS Injection Molded Part.

Glossier surface finishes containing less weld lines can be achieved with high melt temperatures and fast injection speeds.

11.  How Do You Choose An ABS Injection Molding Machine?

A standard ABS Injection Molding Machine contains a compression ratio above 2 with a 20:1 ratio of screw length diameter.

The injection pressure of the machine must also be above 1500 bar for efficient injection molding.

If a high material is required for the ABS color master batch product appearance, then the smaller diameter screw is selected.

ABS Injection molding machine

The clamping force if the machine is usually determined based on the 4700-6200t/m².

This will also be dependent on the product requirements of the ABS Injection Molded part and the ABS grade required.

12.  What Is The Importance Of Pressure In ABS Injection Molding?

Compared to modified polystyrene or basic polystyrene, the ABS melt viscosity is normally high making the injection pressure higher too.

This is specifically applicable to only large and bulky Injection Molded ABS parts.

For simpler and smaller parts that are thick, a lower injection pressure is normally applied.

The workpiece surface quality is usually determined by the cavity pressure when the gate is closed during the injection process

The ABS shrinkage becomes large when the applied pressure is too small and may lead to silver wire defects.

The contact chance with the surface of the cavity becomes large including the atomization of the part surface.

A very high pressure application tends to strengthen the friction between the cavity surface and the ABS plastic.

This easily leads to defects such as adhesion.

Pressure also allows the adjustment of the contraction of the ABS material therefore providing grounds for dimensional correction.

13.  What Are The Precautions To Be Taken During ABS Injection Molding?

There are various ABS grades but caution is mostly taken when dealing with the grade that is flame retardant.

Its melt has a large adhesion to the surface of the screw I the molding machine and takes time to decompose.

When this occurs, the homogenization section should be wiped together with the screws compression pull-out.

14.  What Are The Common Flaws and Their Causes In ABS Injection Molding?

Processed ABS Injection Molded parts may contain the following defects:

• Ultraviolet (UV) Light Degradation: the physical structure of an ABS part can be degraded by exposure to UV light by weakening the chemical bonds.

A chalky surface is one sign that eventually leads to a crack on the surface leading to weakness and part failure.

• Environmental Stress Cracking (ESC): this happens both threshold stress and threshold concentration are applied to the ABS part.

Amorphous plastics like ABS are more susceptible to this type of flaw mostly due to the high stress on extremely sharp corners.

• Cycle Fatigue: this type of failure normally occurs when the ABS part is regularly bent back and forth.

This is majorly due to poor design and hysteretic heat that cannot be thermally discharged by the ABS part.

15.  What Are The Surface Finishes Applied In ABS Injection Molding?

Common ABS Injection Molding Surface finishes include:

Grade A (Gloss Finish)

They are the most expensive type if finish with a glossy and smooth appearance.

This grade requires steel mold tools that are hardened while various types of diamond buff are used.

They do not give the ABS part a clear texture due to buffing paste used (fine grain) and the polishing method applied.

Grade B (Semi-Gloss Finish)

This finish is appropriate for the elimination of tooling, molding and machining marks from the ABS part with minimal tooling costs.

The can be achieved by using different grits of sandpaper through linear motion producing linear patterns.

Grade C (Matte Finish)

Fine stone powder is used to polish the ABS part providing a very economical finish and the most popular finish.

It conceals machining marks while giving a good release. It forms part of the initial surface finishes of grades A and B.

Textured Finish

Being commonly applied in consumer goods and industrial parts, they provide a good aesthetic visual look.

Fine stone powder is initially used to smoothen the part then aluminum oxide dry-blasts it.

The result is a non-directional and smooth surface finish because of randomly dry-blasting the part.

Fingerprint smudges, marks and deformations are easily eliminated while giving it an excellent grip quality.

For any inquiry or questions, contact us now.