Aluminum Die Casting Benefits & Die Life Considerations

If you are considering aluminum die casting for a new part, there are several advantages to doing so. Aluminum die castings are lightweight, corrosion-resistant, has high thermal and electrical conductivity, and are very durable. Aluminum die castings remain strong at high temperatures and retain their dimensional stability even if the part has thin walls or is a complex shape.

Aluminum die castings also have excellent mechanical properties, making it a popular alternative to steel and iron. This is especially true for the automotive industry, which is continually looking for lightweight, durable materials.

Benefits of Aluminum Die Casting

Aluminum can be cast in a variety of ways. The benefit of using the high pressure die casting process over other aluminum casting processes is lower part cost. The aluminum high-pressure die casting process can produce a near-net shape in seconds.

Though high pressure die casting tooling is more expensive than other casting processes, the heat-treated steel and water-cooled die cast die might produce 75K-200K “shots” over its life. And depending upon the part size, geometry, and demand, tools can often be built to produce multiple parts in one “shot,” which further reduces the part price and allows the tooling cost to be amortized over very large quantities of parts.  

Aluminum is the most popular die casting material by far because it is economical and provides a good mix of properties. There are a surprising amount of parts from numerous industries – like automotive, medical, alternative energy – that are cast via the aluminum die casting process due to its many valuable properties.

Aluminum Die Casting and Die Life Considerations

To maximize die life, certain considerations must be taken into account before building the die. Factors that contribute to die life include:

  • The overall design of the part
  • Type of tool used to create the die
  • Configuration of the mold
  • Die steel, heat-treating techniques, and die coatings
  • Expectation for part quality

Before a die is built, the customer first presents a concept or existing part to a die caster. A die cast engineer will assess the project from design to end product and work with the customer to optimize the part design for die casting. An initial discussion with the die caster may include topics such as:

  • Functional and cosmetic requirements
  • Tolerances
  • Annual and lifetime volume
  • Alloy choice
  • Mating parts
  • Project timing
  • Optimizing wall thickness

Importance of Partnering with an Experienced Die Caster

An experienced die caster will take the time to consult with you about your application and assist you with product design. They will then design the tooling to produce parts with repeatable dimensions, excellent surface quality, consistent mechanical properties, and long tool life.  

These factors provide the greatest opportunity for cost savings and maximizing value. A less experienced die caster might offer lower initial costs, but this could cost you in the long run, due to quality, delivery, or tool life issues. A die built to lower specifications will likely fail at an inopportune moment, shutting down production and forcing you to spend much more than what you thought you saved initially.

Contact Chicago White Metal Today

Chicago White Metal Casting (CWM) has 83 years of experience providing our customers with excellent service, saving you money, and resulting in products that you and your customers will love. To find out more about our aluminum die casting service, or other capabilities, contact us online today. You can also reach us at +1 630-595-4425 or via email (sales@cwmtl.com) if you have any questions. You can also click here to request a quote online.

CWM Adds New Idra Die Casting Machine, Full Implementation Planned for Q4 of 2020

Chicago White Metal is extremely proactive in the research of advanced technology and innovation, and their implementation into the die casting process. These efforts are put forth by the company in order to improve and enhance quality, efficiency, measurability, and overall cost savings for existing and future projects.

CWM leadership encourages an environment of cultivating innovative ideas where process improvement is concerned, granting members of the team an opportunity to take an active role in examining and suggesting alternatives to either modify or drastically change current techniques. The team is excited to implement these innovations into the workflow in both traditional and non-traditional ways. 

New Idra Die Casting Machine (2019)

A new Idra Die Casting machine was purchased last year. Extensive planning by the Chicago White Metal team was thoughtfully executed, with full implementation planned for the beginning of Q4 in 2020. This new die casting machine has a 900-ton capacity, which gives Chicago White Metal the opportunity to accommodate substantially larger applications. Although the machine is being installed into the magnesium department, it will initially be used to cast aluminum parts. 

Electric Vehicles: Component Manufacturing Using the High-Pressure Die Casting Process

The automobile industry is the largest market for high pressure die casting components. The demand for electric vehicles has been rapidly growing thanks in large part to changes in emission norms worldwide and a shift in consumer preferences. These changes have pushed automakers to replace heavier components with lightweight, environmentally-friendly options made from alloys like Magnesium or Aluminum.

Reducing weight is significant for hybrid electric, plug-in hybrid electric, and electric vehicles, where battery efficiency is critical. Aluminum and Magnesium die cast components can dramatically reduce vehicle weight, which improves overall vehicle performance, increases fuel or battery efficiency, and extends driving range. Chicago White Metal is helping to fuel this evolution by casting complex shapes at near-net shape in high volumes and within tight tolerances using lightweight alloys.

Aluminum

Automakers who make electric or hybrid cars are increasingly turning to Aluminum due to its combination of excellent mechanical and physical properties at an attractive cost. In addition to weight reduction, high-pressure die cast aluminum alloys have added dimensional accuracy and stability – not to mention the added strength and high-speed production capabilities.

Lighter Weight and Good Malleability

While not as light as Magnesium, Aluminum is still 1/3 the weight of steel, which goes a long way when it comes to reducing the weight of a vehicle. That’s why Aluminum die castings are replacing steel in structural and cosmetic body parts (i.e., vehicle bodies, hoods, doors, bumpers, crash boxes) in modern vehicles.

Malleability is also a significant factor as to why automakers are turning to Aluminum. It can be easily rolled into a sheet, formed as a stamping or extrusion, or welded. And it can be a high-pressure die cast, which allows for the rapid conversion of molten metal to a net shape 3-dimensional complex shape.

Aluminum is excellent for automotive applications when there’s a need for high visibility and structural integrity, such as in A-B-C pillars. While Aluminum is lighter than steel, it absorbs more energy, providing an extra layer of safety for the vehicle as well. Utilizing aluminum components can help reduce vehicle weight by as much as 40% without compromising the safety of the vehicle.

Magnesium

Magnesium was initially used in race cars in the 1920s to gain a competitive edge because of how lightweight it is. Now automakers use this lightweight alloy for applications like mirror housings, steering columns, driver’s airbag casings, seat frames, and dash encasings.

The auto industry’s quest for greater battery and fuel efficiency, along with demand for improved performance, has driven an increased interest in high-pressure die cast Magnesium alloys. These alloys include AZ91D with its excellent combination of mechanical properties and the highest strength to weight ratio of any structural metal.

Mg is 75% Lighter than Steel, 33% Lighter than Aluminum 

Magnesium provides a drastic weight difference that supports its use as a durable metal alternative to steel and plastic. Unlike plastic, Magnesium’s properties do not degrade with temperature and UV light, and Magnesium is 100% recyclable. With its superior dampening capacity and low-mass inertia, Magnesium is well suited for parts designed for frequent and sudden changes in motion direction – making it ideal for car part design. Many part designers also prefer working with Magnesium because they can produce parts that are more complex than steel, without sacrificing strength.

Zinc

Although Zinc products are heavier than their Aluminum and Magnesium-based counterparts, they do have the highest yield strength of all three alloys. Zinc can also be cast thinner than any other metal and can hold extremely tight tolerance requirements. While Zinc might not be the best option when it comes to the light-weighting strategy, several Zinc-made applications are ideal for automotive design and structure.

The CWM Difference

Chicago White Metal Casting can cast all three families of alloys; Aluminum, Magnesium, and Zinc. Our technical expertise, combined with full-service capabilities and engineer design services, can provide automakers or part designers with die casting solutions that meet the challenges of their hybrid electric, plug-in hybrid electric, and electric vehicle part design.

Contact us today by filling out the form on this page or call +1 630-595-4424 to speak with a member of our team.

Click here to download the White Paper .PDF.

CWM Takes Recycling to New Levels

CWM Recycles AL, ZN, and MG
CWM Recycles

As a further refinement to our environmentally responsible culture, CWM has launched a new Recycling Initiative to help take our focus on environmentally friendly manufacturing and overall stewardship to a new level. One of our key objectives is to encourage similar programs with our suppliers, neighbors, and customers.

CWM Recycles Magnesium Scrap

CWM’s recycled materials, such as plastic, steel, cardboard, electronics, etc. are typically sent to a certified recycling vendor. CWM, however, as part of our new Recycling Initiative, is taking the extraordinary step of requiring our recycling vendors to provide a full manifest/certification and/or a detailed process map that illustrates exactly how recyclables are processed. We are finding that not everything is being recycled as we thought. Plans are underway to deal with this issue transparently, and to determine what improvements can be made.

We are also asking our suppliers to provide the recycled content of products sold to CWM. As an example, we asked our food/beverage provider to see if plastic stirrers, lids, utensils, and containers can be replaced with something more environmentally friendly. That effort resulted in eliminating plastic soda bottles (cans and cartons only), changing coffee stirrers from plastic to wood, and replacing foam coffee cups with biodegradable ones.

CWM takes environmental stewardship seriously. We’ve been a leader in our industry in this regard, having had recycling programs in place for more than 30 years. And though we can’t completely overhaul the entire recycling industry on our own, our team will do what we can to initiate changes. We are confident that this renewed Recycling Initiative will have a very positive impact on CWM and our community of suppliers, customers, and neighbors. Stay tuned for more information in the coming months!

CWM and Crossbow Manufacturer Hit the Target with a NADCA Design Award!

CWM CEO and President Eric Treiber accepts NADCA Award
CWM CEO and President Eric Treiber accepts NADCA Award

Chicago White Metal collaborated with a crossbow maker to get a bullseye win for a riser part!  Eric Treiber accepted the award on behalf of CWM for the 2018 North American Die Casting Association (NADCA) Excellence in Design Award, winning the “Aluminum 1 to 10 lbs.” category.

The crossbow manufacturing company was focused primarily on two things: safety and quality.  The riser is a safety-critical part that is the “heart” of the crossbow, so the strength of the part was vital to the success of the end product.  The crossbow was designed to be narrow and made for pinpoint accuracy.  It is one of the lightest crossbows on the market, weighing in at only 6.3 lbs.

Crossbow riser piece cast by CWM

This was the manufacturer’s very first die cast part, which enabled them to convert the “machined from extrusion” approach that they typically do for crossbow risers to a high pressure die casting process.  The design was modified to incorporate as-cast pockets in order to eliminate additional assembly.  Ultimately, the cost was reduced by 1/3 simply by converting to the high-pressure die casting process.

“The Aluminum 1 to 10 lbs category is typically a more competitive category.  That makes the win even more of an honor,” Marketing Coordinator Roseann Rimocal says.

CWM’s internal marketing showcase will display the parts, the end product, and the award for a couple weeks.  The plaque will then be transferred to its new home in the Research & Development wing, along with a number of other design awards Chicago White Metal has taken home over the course of many years.

CWM Industry Spotlight: Robotics

CWM Industry Spotlight: Robotics
CWM Industry Spotlight: Robotics

Industry Outlook

Due to the increasing popularity of automation, the robotics industry continues an upward trend in today’s economy.  Robots take necessary operations and create measurable tasks, which can accurately estimate project timelines.  Robots also perform tasks at a lower cost and allow very little room for error, working in a way that cannot be replicated by a human manufacturing team.  New robot technology is constantly being researched and implemented, allowing rapid growth in capabilities.  Though the robotics industry is generally known for great success in automotive manufacturing, it has given various other industries the benefits of automation.

For example, service robotics are being utilized in government initiatives for military/defense sectors to reduce human involvement.  This would increase the number of unmanned ground vehicles deployed into the front lines, reducing the number of casualties in the face of danger.

The medical industry is another example.  Medical service robots work with MRI, CT scans, fluoroscopy and ultrasound imaging, increasing productivity and decreasing malpractice liability, human error, and the exposure of radiation to human staff.

Robot Usage Chart

Service robotics are estimated to reach $21.7 billion by 2022, with growth over 17.8% from 2015 to 2022.  Medical service robotics sales were just over $2.1 billion in 2014 and are expected to exceed $6 billion by 2022, growing 15% during the forecast period.

The Role of Die Casting in Robotics Products

There are many parts inside of a robot which are ideal candidates for the die casting process.  Aluminum, magnesium, and zinc are the most common alloys in die casting and all three can be used in any type of robotic equipment based on part requirements.  CWM die casts durable components that withstand the wear of repeated tasks, exposure to harsh environments as well as office settings, and protect the delicate electrical work in a robot.

How CWM Contributed Die Castings to the Industry

Chicago White Metal manufactures thousands of parts that have been incorporated into robots.  The CWM engineering team collaborates with customers to produce castings at reduced costs.  These parts are generally high in quality and in strength to protect the delicate electrical work in a robot.

Aluminum for Robotics

ReThink Robotics and CWM

Aluminum A380 is the most frequently used alloy in die casting, offering the best combination of material properties and castability.  Aluminum die castings are used in various industries, including the robotics industry.  CWM casts several components, including housing in the arm, wrist, base, “elbow”, and several other parts of industrial robots.  CWM offers an aluminum alloy data sheet, available for download here.

Aluminum is the ideal choice when the strength-weight ratio is important.  It is about 1/3 the weight of steel and higher tensile strength than cast iron, which are other popular metals used in robot manufacturing.  Of the three, aluminum is the most abundant resource, providing a cost-efficient product.  Aluminum is also an excellent non-magnetic, non-sparking conductor, which makes it suitable for robotic construction.

Magnesium in the future?

Magnesium AZ91D is known for its lightweight properties as a metal.  AZ91D can also be designed for robotic components, when the requirements call for a weight reduction and portability without compromising on material strength and rigidity.  Chicago White Metal can use magnesium in various robotic applications.  For more information on the Magnesium alloy AZ91D, download the white paper here.

If you would like to learn more about the capabilities of die casting and the robotics industry, e-mail us at sales@cwmtl.com or give us a call at 630-595-4424.

CWM Industry Spotlight: Lawn & Garden Industry for Die Castings

CWM Industry Spotlight: Lawn & Garden Industry for Die Castings

Industry Outlook

The lawn and garden power equipment industry is experiencing a steady increase each year, with a 3.2% annual growth rate.  Projections show that at this rate, the industry will reach $11.7 billion by 2019.  While the residential consumer segment still dominates the market, the commercial market has seen an uptick in growth that is clearly outpacing the segment.

The lawn and garden industry includes products such as lawnmowers, turf and grounds equipment, trimmers, edgers, garden tractors, rotary tillers, chainsaws, blowers, vacuums, pruners, sweepers, snow throwers, hedge trimmers, and many other power equipment items.  There is a growing importance within the industry not only for performance, portability, affordability and quality, but also to incorporate environmentally-friendly processes to the manufacturing and assembly of the internal parts of the equipment and machinery.

The Role of Die Casting in Lawn & Garden Products

There are hundreds of components within lawn and garden equipment and vehicles which are ideal candidates for the die casting process.  Aluminum, magnesium and zinc are the most common alloys in die casting and all three are used in a variety of lawn and garden product applications where they provide better overall value than plastic, stampings or machined parts.  Each of the die cast alloys have unique properties that can be used based on the requirements for the parts.  CWM die casts components in all three alloys to meet the durability and high strength demands for outdoor, rugged and long-lasting end products.

How CWM Contributed Die Castings to the Industry 

Chicago White Metal manufactures hundreds of thousands of parts which have made their way into various consumer and commercial applications within the industry.  The CWM Engineering team works with customers to engineer and produce durable, high quality parts at reduced costs.

Aluminum for Encasements

Aluminum A380 is by far the most frequently used alloy in die casting.  This alloy offers the best combination of material properties and castability.  Aluminum alloy die castings are used in a wide variety of industries, including the lawn and garden industry.  CWM casts several components, including gear cases, covers, and several parts which go into a differential assembly. 

Magnesium for Portability

Magnesium AZ91D is the material incorporated into the design of several components for portability because of the alloy’s lightweight properties – a known alternative to plastic but with the strength and rigidity of a metal.  Chicago White Metal uses magnesium to cast parts that are ultimately assembled in lawn and garden end products, including both consumer and professional handheld lawn maintenance equipment.  This bearing cap is part of an assembly inside of a professional hedge trimmer & blower.

Various roll cages have also been produced by CWM, which go into differentials found in commercial and consumer mowers.  Along with the examples given, many other components have been engineered and manufactured by our team to carefully meet the high standards of our customers within the lawn and garden industry.

If you would like to learn more about the capabilities of die casting and the lawn and garden industry, e-mail us at sales@cwmtl.com or give us a call at 630-595-4424.

Hot Chamber vs. Cold Chamber Die Casting

Die Casting 101: Hot Chamber vs. Cold Chamber

High pressure die casting (HPDC) is a process where molten metal is injected under very high pressure into premium steel molds (dies) in order to manufacture high precision die cast products.  The die is designed to cast engineered shapes and complex features with great accuracy and consistent replication.

There are two types of HPDC which Chicago White Metal provides: hot chamber die casting and cold chamber die casting.  Although there are several similarities between the two types, they exist separately for different purposes.

Hot Chamber Die Casting

Hot Chamber Die Casting Process

Hot chamber die casting is a type of die casting that uses alloys with low melting temperatures (i.e. Zinc, some Magnesium alloys).  Using alloys with high melting temperatures would result in
damage to the gooseneck, nozzle, and other components.

In a hot chamber die casting machine, the fixed die half is called a cover die, which is mounted to a stationary platen (large plate to which each die half is mounted) and aligns with the nozzle of the gooseneck.  The movable die half is the ejector die and is mounted to a movable platen, which slides along tie bars.

Hot Chamber Die Casting Process

The metal is contained in an open holding pot, which is placed in the furnace and melted to the needed temperature.  When the plunger is in the “up” position, the molten metal flows into the shot chamber.  As the plunger moves down, it forces the molten metal through a gooseneck and into the die at injection pressures ranging from 1,000 – 5,000 psi.

The machine pushes the moving platen towards the cover die and holds it closed with great pressure until the molten metal is injected.  The plunger remains in the “down” position to hold the pressure while the casting “cools off.”  After solidification, the plunger is retracted and the cast part is either ejected, manually removed from the machine or pushed off the cover die.  This ejection system, which includes an ejector die and ejector pins, allows the casting to be pushed out while releasing the die halves.

Watch an animation of a hot chamber die casting machine:

Cold Chamber Die Casting

Cold Chamber Die Casting Process

Cold chamber die casting is a type of die casting that is used for alloys with high melting temperatures (i.e. Aluminum and some Magnesium alloys).

As a contrast from hot chamber die casting (pumping molten metal into the machine), molten metal is ladled from the furnace into the shot chamber through a pouring hole.  While the general function of the cold chamber machine is similar to hot chamber, cold chamber works with a horizontal orientation and does not have a gooseneck.  

Cold Chamber Die Casting Process

Instead, the plunger forces metal through the shot chamber into the die at pressures ranging from 2,000 and 20,000 psi.  The plunger holds the pressure and retracts after solidification.  The clamping unit and mounting of dies is set up the same as hot chamber, however, the cover die for a cold chamber machine does not have a gooseneck or nozzle, and therefore aligns directly from the shot chamber.

Watch an animation of a cold chamber die casting machine:

If you would like to discuss how CWM can help you with your die casting project, please call 630-595-4424 or contact us at sales@cwmtl.com with your inquiries.

Aluminum vs. Magnesium vs. Zinc: Alloy Properties in a Nutshell

CWM Employee working on Aluminum Die Cast Filling

Aluminum, magnesium, and zinc are the most common alloys used in the die casting process.  Aluminum and magnesium are considered to be relatively “lightweight” metals, and zinc alloys are a preferred metal to use in the miniature die casting processes and applications requiring thinner walls.

Deciding which alloy is best suited for a specific application of a die cast part is usually based on the design specifications – the alloy usually provides physical and mechanical properties that fit the end product application.  It is important for a product designer seeking a die casting supplier to understand each type of alloy being offered and what benefits are involved.

Aluminum Die Casting Alloy

Aluminum is by far the most frequently used alloy in die casting.  The most common aluminum die casting alloy is A380, which offers the best combination of material properties and castability.  Aluminum alloy die castings are used in a wide variety of industries.  It is common to see this alloy in electronics, communications equipment, automotive components, gear cases, lawnmower housings, hand and power tools, and many other products.

There are a number of aluminum alloys used in die casting.  Each alloy has its own unique set of properties.  Aluminum alloys for die casting have superior machining characteristics in comparison to iron, steel, and titanium.  Amongst the other types of aluminum alloys, A380 has better than average machining characteristics.

Magnesium Die Casting Alloy

Magnesium Die Cast parts

Magnesium alloys are the lightest of the commonly used structural metals used for die casting.  Magnesium alloy AZ91D offers the highest strength of all commercial magnesium die casting alloys.  It is also the most widely used.  AZ91D Magnesium is a high purity die casting alloy which offers the following qualities:

  • Excellent Corrosion Resistance
  • Excellent Castability
  • Excellent Strength

Corrosion resistance is achieved by enforcing strict limits on three metallic impurities: Iron, Nickel, and Copper.

Some of the more common applications for magnesium die castings are:

Automotive: cam covers, steering columns, steering wheels, brake and clutch pedals, clutch housings, seat frames, and dashboard supports; Portable tools such as chain saws, drills, grinders, lawnmowers, string trimmers and pruners; portable electronics such as projectors, cameras, radar indicators, calculators, and navigation devices; telecommunications equipment, levels; and recreational products such as snowmobile components, archery bows, spotting scopes, etc.

While there are special precautions to take when machining or grinding magnesium die castings, magnesium alloys machine easily, requiring less power to machine than the other die casting alloys.

Finishing magnesium castings is similar to other alloys and any special treatments and coatings are usually taken into account when considering the end product and application.

Zinc and ZA Die Casting Alloys

Zinc Die Cast

Zinc and ZA alloys are commonly used for smaller die castings or die castings that require thinner sections.  Zinc alloys generally allow greater variation in section thickness and can maintain closer tolerances.  The impact strength of zinc die cast components are higher than the other common metal alloys, with the exception of brass.  Also, because Zinc and ZA alloys require lower pressure and temperatures in comparison to magnesium and aluminum alloys, the die life is significantly longer and maintenance is relatively minimal.

Zamak alloys all contain approximately 4% aluminum and a smaller percentage of magnesium to make sure strength, hardness, and corrosion resistance properties can be achieved.

When it comes to miniature die castings, zinc is definitely the route to take.  Miniature zinc die castings can be produced at high volume using special hot-chamber die casting machines that yield castings which are flash-free, with minimal draft and very close tolerances, requiring no secondary trimming or machining.

Zamak #3 is the most common of the Zinc alloys for die casting, offering the best combination of mechanical properties, castability, and economics.  These zinc alloy metals have the ability to produce castings that have intricate details and surface finish at high production rates.

ZA alloys have more aluminum and copper content in them than the Zamak group for several reasons:  higher strength, superior wear resistance, superior creep resistance, and lower densities.  ZA-8 is the sole ZA alloy that can be die cast by the faster hot-chamber process.

Machining characteristics of Zamak and ZA are very good and both alloys have the ability to accommodate high-quality surface finishes when routine guidelines for machining zinc are followed.

Striko Dynarad & Nicor Gas both feature the newest CWM Aluminum Melting Furnace

Newest CWM Aluminum Melting Furnace
Newest CWM Aluminum Melting Furnace

Striko Westofen, a global manufacturer of thermal processing technology, is known for providing energy-efficient solutions for various types of casting industries, which includes aluminum die casting.

Just recently, Striko featured Chicago White Metal in their latest website article about our latest aluminum furnace addition.  This article features the new aluminum melting furnace installation that CWM recently acquired in response to the significant growth in aluminum die castings demand, to increase our aluminum melting capacity, and to maintain our responsibility to the environment as a part of the CWM culture.

Nicor Gas energySMART program, in conjunction with Striko Westofen, has also featured Chicago White Metal in their latest publication regarding the latest installation of the Striko aluminum furnace. Nicor describes the details on its energy efficiency in day-to-day die casting operations, providing benefits to both CWM and to our environment.