At Kanthal, a global leader in electric heating technology, quality testing is much more than a box-ticking exercise. It is a rigorous, evolving process built on decades of innovation, material expertise, research, and attention to detail.
Thomas Lewin, Senior Design Engineer at Kanthal, emphasizes the significance of these evaluations. "Our tests ensure that the materials we produce meet the highest standards," he explains. The company employs a comprehensive testing approach, which includes bash tests, furnace tests, and many others, designed to push the materials to their limits while continuously enhancing their performance.
Understanding the bash test
Thomas Lewin, Senior Design Engineer, Kanthal.The bash test, a centerpiece of Kanthal’s quality assurance program, is a slightly modified version of the standard methods tailored specifically for the company’s iron-chromium-aluminum (FeCrAl) alloy portfolio. According to Lewin, the standard procedure was “too kind” for these materials, leading Kanthal to adapt the test to achieve more accurate results.
“The process begins with a wire, usually, 0.70 mm in diameter, shaped into a U-form and mounted between two terminals. Power is then applied to the wire, cycling the temperature between 850°C and 1,100°C (1,562°F and 2,012°F). Each cycle consists of two minutes of heating followed by two minutes of cooling, continuing until the wire eventually breaks,” he explains.
“The duration until breakage provides crucial data on the wire’s durability. We also use it to assess how the material ages under stress, gaining valuable insights that help us refine and further develop our materials,” states Lewin.
The furnace test: Industrial-grade evaluation
While the bash test is essential for understanding domestic appliance applications, Kanthal developed the furnace test to evaluate materials used in industrial heating settings. This test operates on a similar principle but under much harsher conditions.
“Rather than using wires with a diameter of 0.70 mm, the furnace test employs wires with a diameter of 4 mm, which are more suitable for industrial-grade applications. The temperature cycles range from 900°C to 1,300°C (1,652°F to 2,372°F). Additionally, the surface load increases significantly from 11 watts per square centimeter in the bash test to 17 Watts per square centimeter in the furnace test,” explains Lewin.
Despite these differences, the goal remains common: to measure the lifespan and map how different alloys behave under extreme conditions. Lewin adds, “This test is strictly for research and development purposes. It allows us to push our materials further and ensure they meet the exacting demands of industrial use.”
Evolving with industry demands
Kanthal’s testing methods are not static. As industries continually transition from gas to electric heating, the expectations from materials continue to grow. Meeting these demands requires a combination of material innovation and advancements in testing and regulation technologies.
Traditional tests typically use on/off power cycling. However, Lewin advocates for technologies like thyristors. “This would allow us to simulate real-world conditions better and enhance our material know-how,” he explains.
Continuous improvement: A way of life
Identifying and addressing weaknesses early ensures that our materials meet the highest standards before they reach our customers.
Kanthal’s existing material portfolio results from decades of rigorous testing and refinement. “Each alloy undergoes extensive trials,” Lewin explains, adding that the results can vary depending on its specific composition. Despite this variability, Kanthal’s materials are expected to set the benchmark for performance.
Yet, even for the industry leader, challenges arise.
“Sometimes we find that even our alloys are not OK,” Lewin acknowledges candidly. These moments, though rare, emphasize Kanthal’s pursuit of excellence.
“When issues arise, the team ascertains the root cause, investigating whether adjustments in the manufacturing process can resolve the problem or if the material needs to be discarded entirely,” he adds.
Lewin emphasizes, “Identifying and addressing weaknesses early ensures that our materials meet the highest standards before they reach our customers.” This process safeguards product reliability and strengthens customer trust.
A holistic quality program
In addition to development-focused tests, Kanthal conducts several delivery-oriented evaluations. “We use tests like hardness testing, surface defect analysis, and structural evaluations to verify the mechanical and surface properties,” Lewin shares. He also highlights the importance of resistance-related metrics, such as the Temperature Coefficient of Resistance (TCR) to determine how resistance changes with temperature and under different conditions.
Another key R&D-specific evaluation is the creep test, especially relevant for industrial-grade alloys. “The creep test measures how well an alloy can withstand prolonged stress at high temperatures and is crucial in developing cost-effective alternatives to nickel-chromium alloys,” Lewin explains.
“We try to reduce the cost for the alloy but still aim to achieve the same creep property strength,” he adds, underlining the balance between affordability and performance.
“Not every batch undergoes every test,” Lewin clarifies. He also highlights the role of automation in streamlining these processes. “We’ve implemented advanced systems, like lasers for monitoring wire dimensions, which allow us to conduct 100 percent testing of critical parameters,” he says. “Automation has significantly improved our ability to ensure quality while optimizing efficiency.”
Application-specific testing for customer needs
Every application has unique demands and meeting them requires more than just high-quality materials—it calls for stringent evaluations and effortless integration of all components. Kanthal’s application testing lab is central to this effort, enabling the development of tailored solutions that align perfectly with customer needs.
“Our lab enables us to tailor solutions to meet specific requirements. For example, in a project involving furnaces with 200 to 300 heating units, every detail is scrutinized. It's not just about testing the materials; we assess installation methods, control systems, and overall functionality to ensure that everything works together as a unified system” Lewin highlights.
Constant improvement and adaptability have enabled Kanthal to establish itself as a trusted name in heating technology for industries worldwide. As industrial applications become increasingly complex, Kanthal continues to evolve, ensuring its alloys are ready to meet these demands.
The goal remains as clear as ever: delivering solutions that stand the test of time.