As a Custom Opportunities Manager at Goodfellow, I'm constantly impressed by the sheer versatility and advanced capabilities of ceramic materials. Often, when people think of ceramics, images of pottery or everyday tableware might come to mind. However, the reality is that modern technical ceramics are at the forefront of innovation across a vast spectrum of industries, offering a unique combination of properties that are simply unmatched by other material classes.
At Goodfellow, we pride ourselves on offering a comprehensive range of ceramic materials, catering to diverse and demanding applications. What sets ceramics apart? Primarily, it's their exceptionally strong ionic and/or covalent bonds, which are significantly more robust than those found in metals. This fundamental characteristic underpins the properties we commonly associate with ceramics: high hardness, high compressive strength, low thermal and electrical conductivities, and excellent chemical inertness.
Our portfolio includes both traditional and advanced engineering ceramics. For instance, we offer Alumina (85% upwards), a material often manufactured by pressing, machining in its "green" state, and then firing. Different grades of Alumina exhibit varying properties like hardness, thermal conductivity, electrical properties, and strength, making it suitable for a wide array of uses. Similarly, Zirconia, another ceramic we supply, follows a similar manufacturing route and is available in different grades (Yttria stabilized, Magnesia stabilized) with tailored strength and fracture toughness.
One of the key advancements in the field has been the development of machinable ceramics. Traditional ceramics typically require costly diamond grinding after firing. However, materials like MACOR® machinable glass ceramic offer a game-changing alternative. This unique material, composed of approximately 55% Fluorophlogopite mica and 45% Borosilicate glass, can be machined with ordinary metalworking tools to achieve high precision components without the need for post-firing. MACOR® also boasts excellent electrical properties, providing good insulation at high voltages, frequencies, and temperatures, and it will not outgas in vacuum environments when properly baked out. Its maximum use temperature is 1000 °C. We offer MACOR® in various forms, including rods, bars, and sheets.
Another noteworthy machinable ceramic in our offering is Shapal Hi M Soft (Machinable Aluminium Nitride). This composite ceramic of AlN and BN is hard yet machinable with carbide-tipped tools. A significant advantage of Shapal® Hi-M Soft is its high thermal conductivity, approximately 5 times that of Alumina. It also exhibits excellent mechanical properties and is well-suited for applications requiring both electrical insulation and heat dissipation. Its maximum operating temperature reaches 1020 ºC in air and an impressive 1900 ºC in a non-oxidising atmosphere.
Beyond machinability, ceramics excel in various other areas. Many offer superb high-temperature performance. For example, Alumina can withstand temperatures up to approximately 1600ºC, while Fused Quartz and Fused Silica, though technically glasses, boast maximum recommended temperatures of 1200 ºC. Sapphire can operate at temperatures exceeding 1800 ºC. Boron Nitride also demonstrates good thermal conductivity while being an electrical insulator. Certain ceramics like Silicon Nitride exhibit high fracture toughness and good thermal shock resistance.
In terms of electrical properties, many ceramics are excellent insulators. However, some, like Shapal® Hi-M Soft, become electrically conductive above about 500 ºC. Silicon Carbide is also electrically conductive, particularly at elevated temperatures. These varying electrical characteristics make ceramics indispensable in electronics and electrical engineering.
Mechanically, ceramics like Boron Carbide are extremely hard and are even used for ballistic armour protection. Silicon Nitride also stands out as a hard ceramic. The mechanical strength of materials like MACOR® and Shapal® Hi-M Soft allows for their use in demanding engineering applications.
At Goodfellow, we understand that every application has unique requirements. That's why we offer custom ceramic components and provide expert technical support on material selection and component design. Our experienced team can guide you in selecting the most appropriate ceramic material and the most cost-effective manufacturing route. We offer a wide range of services, including machining, laser cutting, grinding, and polishing to achieve your specific tolerances and surface finish requirements.
When you're considering ceramics for your next project, it's crucial to think about factors like maximum operating temperature, operating conditions, and required tolerances. Providing us with these details allows our team to help you pinpoint the ideal material for your specific needs.
In conclusion, the world of ceramics is vast and full of potential. From their inherent strength and thermal stability to the advancements in machinability, these materials offer engineers and researchers a powerful toolkit for innovation. At Goodfellow, we are committed to providing high-quality ceramic materials in a multitude of forms, coupled with expert support, to help you push the boundaries of what's possible. Don't hesitate to get in touch with our team to discuss your specific application and discover how our ceramic solutions can benefit your work.
– Adam Sells
