A20X / 205 / AMS4471 Aluminum Alloy

The 200-Series of Aluminum-Copper alloys, such as A201-T7, are well known for very high strength; nearly double that of the more common 300-Series of Aluminum-Silicon alloys. Although O’Fallon Casting does cast A201, the propensity of the Aluminum-Copper alloys to “Hot Tear” during solidification has limited their widespread use. The Investment Casting industry in general considers these 200-Series alloys to be “un-castable”. 

Aeromet International PLC has overcome this obstacle with development of a truly castable 200-Series alloy, A20X, widely regarded as the strongest commercially available cast aluminum alloy in the market today. The FAA added 205-T7 to the MMPDS in 2013. SAE International has issued specification AMS 4471A for the Investment Casting of 205-T7 alloy with minimum physical properties that exceed those of cast alloys A201-T7 (AMS 4229), E357-T6 (AMS 4288) and A357 (AMS 4219). OFC has tested 205-T7 and has substantiated the physical properties of AMS 4471A.

O’Fallon Casting has been licensed by Aeromet International PLC to manufacture castings from their patented A20X / 205 aluminum alloy (AMS 4471A).

In addition to its high ambient temperature properties, A20X also has outstanding Elevated Temperature Strength, Fatigue Strength and Corrosion Resistance.

The 205-T7 will challenge alloys such as D357 & E357 for use in “Structural Casting” applications. The high properties of 205-T7 will also serve as an alternative to wrought alloys for configurations that are difficult or impossible to machine.

Although it is unlikely to replace an industry standard such as A356 in “everyday applications”, 205-T7 should be considered for use in products where the strength vs. weight ratio is a crucial consideration such as in Aerospace & Transportation.

Potential Customers will want to “Qualify” 205-T7 for use in their products and O’Fallon Casting is interested in working with partners to help develop new designs for the alloy.

For further information, contact O’Fallon Casting.

Customer Quality Cross Training

The Sales Engineering team at O’Fallon Casting acts as the primary point of contact between the business and its customers. Because of this, it is critical that all of the technical and quality requirements of customer products are understood by each Sales Engineer. Additionally, the Sales Engineer is responsible for verifying the contract requirements and ensuring that they are met. They essentially, acts as the program manager for the customer at the foundry. This past February 11^th-13th, O’Fallon Casting had the opportunity to send one of its Sales Engineers to take part in a three day quality training course hosted by one of its aerospace customers.  Typically, this course is only open to Quality Engineers or Quality Assurance representatives. O’Fallon Casting, however, requested that their Sales Engineer be allowed to take part in the training in an effort to promote cross training. OFC felt that this training course offered a superb opportunity for its Sales Engineer to be exposed to its customer’s quality organization and quality requirements.

               The three day training session took place in Anaheim, CA. The sessions are typically offered once a month in varying locations. About thirty five Quality Representatives from various suppliers were in attendance. Each day lasted eight hours and was comprised of a combination of lectures, question and answer sessions, and assignments. Coursework covered a wide array of topics including First Article Inspections, Part Marking, Product Safety, and Special Processes. Each topic covered customer specific instructions and preferences for each process. There was even an opportunity to prepare an entire mock First Article Inspection package using the customer’s procedure. This provided vital insight into how this customer accepts inspection data. In turn, this training will enable streamlined qualification of new castings to our customer. Now that the Sales Engineer is more familiar with their processes, design and inspection data can be better communicated to their engineering and purchasing teams. Individualized customer training in inspection and part qualification is important as each company has a different qualification process to follow. O’Fallon Casting encourages other companies to provide similar training.

               Now that the Sales Engineer is course certified, he can act as a better liaison between OFC’s Sales and Quality departments. Furthermore, the way our customer handles and resolves quality issues can be better understood. This is extremely beneficial for communication between OFC and its customers. This valuable experience demonstrates the need to expand these classes to supplier employees outside of the quality organization. Contract officers, manufacturing engineers, and other critical employees all act in the production of customer product and can benefit from this exposure.  This training experience demonstrates O’Fallon Casting’s commitment and dedication to our customer’s and their requirements. We are willing to go the extra mile and put forth every effort in meeting your product’s needs.

The High Cost of Part Count

One sometimes overlooked aspect of part design is the High Cost of Part Count, that unintended cost for NOT combining the assembled features of a system into a single piece structure. One of the strengths of the casting processes, and in particular that of Investment Casting, is the ability to combine multiple features into one consolidated design that reduces the Part Count and enhances both the affordability and reliability of a system.

 

Simply stated, Part Count is “the total number of separate parts in an engineered system” and there are numerous articles and abstracts available concerning the subject. Many businesses do utilize Part Count as a design-to-cost factor, but I am also surprised to find that some do not.

  

If you consider the “Cost Stream” for any single part in a system, the accumulated cost for procurement can be staggering. Here’s a short list of downstream costs for each new part design:

• Design Approval, Data & Control and the Make / Buy Decisions 
• Production Planning, Purchasing Requisitions and Purchasing
• Tooling Construction and Proofing
• Manufacturing, Inspection and Testing
• Shipping, Receiving, Inspection and Inventory
• Part Assembly and Testing  

When you consider the duplicative costs that are absorbed for each individual part in a system, it is easy to understand the value of a lower Part Count. Even in an instance where the per-unit-price of a complex part might be greater than the total of multiple simplified pieces, there is still inherent value in designing them into a single cast structure.

 

Furthermore, every assembly point in a system does carry some risk of system failure that impacts warranty costs. A lower Part Count, which is the result of fewer assembly operations, should also improve system reliability.

Often Part Count reduction only becomes a consideration once a system is in the field. At this late point, however, the costs for redesign, additional tooling and testing will often discourage effective action. Part Count reduction, therefore, is most effective if implemented early in the design process at the point where the System Assembly points are identified. Concurrent Engineering input from a foundry can be invaluable at this point.

Generally speaking a lower Part Count can enhance both the affordability and reliability of a designed system. Castings are an effective design option to eliminate assembly operations and reduce a system’s Part Count. 

Casting design does, however, require some specialized expertise. To that point O’Fallon Casting provides its customers with Concurrent Engineering Services to assist them in reducing the Part Count of their systems. OFC also offers its Investment Casting-101 class to teach the basics for good casting design. 

If you have any questions, contact your O’FallonCasting Sales Engineer.

What is an Investment Casting?

Investment Casting is a foundry process known for producing highly accurate, near-net-shape, castings.  Once known as the “Lost Wax” process, much as Sand Castings are produced from sand molds, and Die Castings are manufactured from metal dies, Investment Casting derives its name from its ceramic molding material that is known as “Investment”. 

A technical definition of the Investment Casting process is “A foundry process by which a metal part is produced from a ceramic (Investment) mold that was formed by a heat-disposable (wax or plastic) pattern.  The earliest known evidence of the Investment Casting process was more than 5000 years ago in ancient China.  Other early civilizations in Asia, Africa, Europe and the Americas are also found to have utilized the process. 

Through most of history Investment Casting was largely used for the manufacture of custom jewelry, sculpture and art.  However, in the 1930’s the Investment Casting process was rediscovered when its ability to cast near-net-shape parts was found to be advantageous for the manufacture of components for aircraft & arms during World War II.

Following the War, the use of Investment Casting began to expand into broader markets.  In 1953 a coalition of Investment Casters, and their suppliers, formed the Investment Casting Institute which then established design guidelines to aid Engineers to better design for the process

Today, Investment Casting foundries exist in many countries around the globe, serve in a vast array of markets and are manufactured in a stunning variety of metals.  O’Fallon Casting itself specializes in the Investment Casting of Aluminum, Brass, Bronze and Silicon Carbide / Metal Matrix Composite alloys. 

Engineers continue to discover the ability of the Investment Casting process to manufacture highly detailed and accurate shapes that reduce weight, improve functionality, or reduce part count. 

If you have any questions, please contact us at:   sales@ofalloncasting.com

Characteristics of Casting Design – AFS Video

O’Fallon Casting was pleased by a video that has been released by the American Foundry Society on their MCTV – Metalcasting Television.  In the video design engineering consultant and author, Jiten Shah, a Product Development Analyst expounds on design elements of O’Fallon Casting’s “Casting of the Year”.

Jiten Shah skillfully promotes aspects of “Good” casting design such as the combining multiple pieces into one cast structure.  He also hits upon some of the distinct advantages of the Investment Casting process such as surface finish and zero draft.

O’Fallon Casting is delighted to have been selected as winner of the AFS / Metal Casting Design & Purchasing 2013 Casting of the Year award.  However, winning the award first required that a Design Engineer envision the cast part and then “put the black lines on the white paper”. 

To promote good casting engineering and design, O’Fallon Casting offers its Investment Casting-101 class to its customers.  IC-101 explores, in detail, the fundamental principles and considerations for successful casting engineering.

We thank Jiten Shah for his kind and incisive comments about the casting, and the American Foundry Society for sponsoring the video.

http://www.afsinc.org/multimedia/MCTVDetail.cfm?ItemNumber=15468#.UkGrj-riZWo.email