In the latter half of the 20th Century, 3D printing was born. At the time, the process was known as stereolithography (SLA) or rapid prototyping (RP). Inventor Charles (Chuck) Hull coined the term SLA in 1984 and was granted a patent for the process in 1986. Shortly after, Chuck co-founded the world’s first 3D printing company, 3D Systems Corporation, to commercialize it. From humble beginnings, the company went on to produce the first 3D printer in 1987, the SLA-1. Chuck himself admitted that he had no idea just how much of an impact his creation would have on the modern world.
SLA was an earlier form of the 3D printing process, and since its conception over 30 years ago, has undergone rapid and advanced development. Over this time frame, improvements to the 3D printing process have allowed manufacturers from a variety of industries to design and make products faster, improve the efficiency of product design, fabricate parts on demand, and improve how tools are made. In this article, we will provide a brief overview of how the design of products has changed with AM.
Design and Redesign Freedom
3D printing, which is also known as additive manufacturing (AM) is the “process of joining materials to make objects from 3D model data, usually layer-upon-layer, as opposed to subtractive manufacturing methodologies, such as traditional machining” as defined by the ASTM International Committee F42 on Additive Manufacturing Technologies. Compared to traditional manufacturing processes (subtractive manufacturing (SM) and formative manufacturing) which can either involve material removal by machining, drilling, or grinding or by casting into molds, AM allows for a greater level of design freedom. The entire process incorporates a range of manufacturing techniques including powder bed fusion, directed energy deposition, material extrusion, binder jetting, curing, lamination and more. This variety has allowed a vast array of technologies to be developed that may be of interest to worldwide industries. AM has enabled complex geometries to be incorporated into the design of products which would otherwise not be possible with traditional manufacturing.
The redesign of parts has been made more efficient with AM. If a change in the design of a particular part is needed on a production line, the computer model used to print the part can be remodeled and redeployed for printing. The standard file used for 3D printing is a standard triangle language file (STL). This STL file usually contains a triangulated representation of a 3D computer-aided design (CAD) model for a given part. The modification of this design step in the production process for AM systems allows parts to be produced without the change in tooling or mold required, which would be costly and more time-consuming than with traditional manufacturing.
Speed of Production
In terms of large-scale manufacturing, companies and organizations working across a number of different industries have been able to use AM to speed up the time it takes to manufacture a product in order to get it to the market ahead of time. This can provide companies a competitive edge and help to satisfy consumer needs.
In a production line that is integrated with AM system processes, improvements to machinery, change in print speed and change in product design can be altered much more easily than with conventional manufacturing methods. A change to product design that could once have taken several months can be cut down to weeks or even days.
One example of the rapid movement of a product to market and its production on a larger scale can be seen in the design of medical equipment during the earlier stages of the year 2020. During the initial stage of the coronavirus pandemic, Texas A&M University and Houston Methodist Hospital entered into a partnership. Texas A&M created and provided 3D-printed spacer/diffusers for metered-dose inhalers (MDI) used by Houston’s medical staff. The MDIs were used to treat patients diagnosed with COVID-19 and those suspected of having the virus.
Material, Process, and Energy Cost Savings
By eliminating the need for material subtraction and additional tooling as required in conventional manufacturing, AM has been making the process of production more material-efficient. With regard to the low volume production of products, AM provides more substantial savings for manufacturers as the actual processing methods and metal powder production are quite high on energy-consumption.
In a review article centered on AM for the aircraft industry, one of the greatest benefits of AM has been the ability to manufacture more light-weight parts. The reduction in weight of parts incurs tangible savings on fuel across the full lifespan of an aircraft. A Bleed Air Leak Detect (BALD) bracket used in the hot side of the engine on Lockheed Martin’s Joint Strike was created using an AM technique known as electron beam melting. This process has been shown to reduce the buy-to-fly ratio to 1:1, instead of 33:1 attributed to traditional methods. This corresponds to a saving of 50% with regard to the titanium alloy used. The buy-to-fly ratio is a term used in the aerospace industry that refers to the weight ratio between a finished component and the original raw material.
Further cost savings have been made through the implementation of AM where multiple parts have been produced together within a single, complex piece. This is in contrast to traditional manufacturing, where it is customary for multiple parts for a specific product to be made individually. Other features required for assembly of the end product such as brazing or welding and fasteners have now been removed from the process with AM, further cutting production costs.
Looking to the medical sector, AM has been a revolutionary force in the construction of truly customized prostheses for patients suffering from a variety of maladies. MT Ortho, an Italian supplier and manufacturer of medical devices combined CT imaging and AM to create such innovative patient-centered devices.
The company began its exploration with AM in 2014, and have developed its range of products from customized prostheses for neurosurgical applications and oncological orthopedics, to maxillofacial surgery and more. One of the company’s most recent developments has been the manufacturing of cancer prosthetics for bone carcinomas or chondrosarcomas. Following demolition surgery where a tumor is removed, medical and design experts have been able to combine forces and completely reconstruct the bone anatomy of individual patients. CT scanning is an essential initial stage in the AM process which is able to capture the specific anatomical characters of the patient to build an accurate 3D model for their prosthesis.
AM has and continues to change the way products are designed and manufactured through continued research and development of the process. For some 3D printing technologies, the successful printing of a part relies on supports that maintain its structure and integrity. Without supports for the creation of certain structurally unstable parts, end products can fail due to deformation and collapse during the printing process. Despite the need for part supports, they require more time and cost to integrate into part designs, can cause damage to parts during post processing, and limit the geometric complexity of part design.
A recent development in AM technology known as support-free AM is a process that involves the removal, reduction or optimization of support structures to overcome such issues. This mode of manufacturing could enable a new wave of 3D printing that promotes successful part design and production as well as minimize challenges concerning the verification of part functionality in the future.
To find out more about how additive manufacturing can be beneficial for your project contact us today and we will help guide you on your journey.