{"id":1520,"date":"2020-02-04T16:52:00","date_gmt":"2020-02-04T16:52:00","guid":{"rendered":"https:\/\/sybridge.com\/?p=1520"},"modified":"2023-06-28T02:00:15","modified_gmt":"2023-06-28T02:00:15","slug":"everything-ultem","status":"publish","type":"post","link":"https:\/\/sybridge.com\/everything-ultem\/","title":{"rendered":"Aerospace Meets Additive: Everything You Need to Know About ULTEM (PEI)"},"content":{"rendered":"\n

Previously published on fastradius.com on February 4, 2020<\/em><\/p>\n\n\n\n

An Introduction to ULTEM Plastics<\/h2>\n\n\n\n

High-performance plastic polymers fall into two categories: thermosets and thermoplastics. Thermosetting polymers are those that solidify to an irreversible hardness after curing due to chemical bonds within the plastic. The polymer hardens in a cross-link pattern that prevents it from re-melting, even under extreme heat.<\/p>\n\n\n\n

ULTEM\u00ae, the branded name for polyetherimide (PEI), is one of the few commercially available amorphous thermoplastic resins that retains its mechanical integrity at high temperatures. Initially developed by General Electric Plastics Division (now SABIC<\/a>) in the early 1980s, ULTEM is a high-performance plastic that has been a staple of the manufacturing industry for over 35 years. This material is strong, chemical- and flame-resistant, easy to use, and able to withstand extremely high temperatures while retaining a set of stable electrical properties.<\/p>\n\n\n\n

Often used in the production of circuit boards, eyeglasses, food preparation and sterilization equipment, and, perhaps most notably, aircraft parts, ULTEM is known for its strength and durability. Read on to find out everything you need to know about ULTEM.<\/p>\n\n\n\n

Printing With ULTEM<\/h2>\n\n\n\n

ULTEM is easy to thermoform and can be manufactured using fused deposition modeling (FDM). A heated nozzle repeatedly follows a set toolpath and emits one layer of the material at a time until the product is fully formed. <\/p>\n\n\n

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Photo credit: Stratasys<\/em><\/figcaption><\/figure>\n<\/div>\n\n\n

Injection modeling is another quick and cost-effective option for manufacturing with ULTEM. Thermoplastic pellets are fed into the injection molding screw, melted and injected into the mold, cooled and hardened, then the completed part is pushed out via the ejector pin. This process is ideal for production of uniform parts in high quantities, such as burn-in sockets.<\/p>\n\n\n\n

Mechanical Specifications<\/h2>\n\n\n\n

ULTEM stands out from other high-performance polymers because it is uniquely designed to remain mechanically stable under extreme conditions. It can withstand temperatures upwards of 217\u00b0C for extended periods of time and remain dimensionally stable in fluctuating temperatures. It is inherently flame resistant and produces minimal smoke that is no more toxic than smoke produced from burning wood.<\/p>\n\n\n\n

Amorphous thermoplastics have the tendency to crack when they come into contact with fats and oils from food, alcohols, acids, fluids used for servicing cars and aircrafts, and other aqueous solutions. Not only can ULTEM resist stress cracking under such conditions, but it is also resistant to ultraviolet rays and gamma radiation.<\/p>\n\n\n\n

ULTEM\u2019s key mechanical specifications include:<\/p>\n\n\n\n