Laboratory Furnaces FAQs
What is a laboratory furnace?
Laboratory furnaces are specialised high-temperature equipment for various research, development, and industrial applications. They are an essential part of any lab, designed to create an extremely precise and uniform heating environment for heating, melting, evaporating, or decomposing a wide range of materials.
What is the temperature range of a laboratory furnace?
Understanding the heating range you will work on is critical for choosing the correct furnace. For most furnaces on the open market, the temperature range is 1000°C – 1800°C. Lab furnaces that can reach a higher temperature will cost you more.
If you’re working in the 1000°C – 1200°C range, a furnace with a metallic heating wire will suffice, but reaching 1600°C will require a furnace with a silicon carbide heating element.
If 1800°C is your target, you will need a furnace with a molybdenum disilicide heating element.
What are the different types of laboratory furnace?
Understanding your application needs will help you select the right furnace to achieve precise and reliable results. Here’s a quick breakdown of the different types used across a vast range of industries for manufacturing or testing:
Ashing furnaces – These high-temperature ovens allow materials to be burned in an enclosure at a closely controlled temperature until only ash remains. They enable researchers and scientists to carry out ash and combustion analysis in samples such as coal, food, and soil.
Muffle furnaces – Also known as a box or laboratory chamber furnace, muffle furnaces provide a controlled environment for heating samples where the material being treated doesn’t directly touch the heat source. These high-temperature heating devices are typically electrically powered and offer versatility for applications like ashing, brazing, heat treatment, and sample drying.
Tube furnaces – Characterised by a central tube surrounded by a cylindrical chamber with heating elements, a laboratory tube furnace provides rapid heat-up, controlled heating up to high temperatures, and fast cool-down. They’re ideal for applications requiring uniform heating under controlled atmospheres like annealing and chemical vapour deposition.
Vacuum furnaces – Commonly used in advanced materials research, vacuum furnaces are engineered for superior temperature uniformity and repeatability. They operate in oxygen-free environments, preventing oxidation and contamination during heat treatment.
This enables clean and precise treatments like brazing and sintering, making them indispensable to the aerospace industry for manufacturing critical components with exceptional mechanical properties, like engine parts and turbine blades.
Which industries use laboratory furnaces?
Laboratory furnaces are used in a wide range of industries, including:
- Materials science: Laboratory furnaces are used in materials science research to study the properties of various materials, including metals, ceramics, and polymers.
- Chemical and pharmaceutical: Laboratory furnaces are used in the chemical and pharmaceutical industries to synthesise and purify chemicals, and test the stability and purity of drugs.
- Electronics: Furnaces are used in the electronics industry to manufacture and test electronic components, such as semiconductors and microchips.
- Environmental: Laboratory furnaces are used in environmental research to study the effects of high temperatures on soil, water, and air samples.
- Food and agriculture: Furnaces are used in the food and agricultural industries to test the nutritional content and quality of food products.
- Geology and mining: Furnaces are used in geology and mining research to study the properties of rocks and minerals.
- Energy: Laboratory furnaces are used in the energy industry to test the performance and efficiency of energy-related products, such as batteries and solar cells.
- Aerospace: Furnaces are used in the aerospace industry to test the strength and durability of materials used in aircraft and spacecraft.
Common uses of laboratory furnaces
Laboratory furnaces are essential for various applications in science, industry, and research. They provide precise temperature control and a controlled environment for numerous processes, making them valuable equipment in any laboratory setting.
Some common uses for laboratory furnaces include:
- Heat treatment of metals and alloys: Laboratory furnaces heat materials to high temperatures to alter their microstructure and properties. It can strengthen metals, improve their corrosion resistance, or change their electrical or thermal conductivity.
- Ceramics processing: Laboratory furnaces are used to sinter ceramics, which involves heating them to high temperatures to create a solid, homogenous mass. This process creates various products, including structural and refractory ceramics, catalysts, and electronics.
- Ashing: Laboratory furnaces are used to burn organic materials to analyse their composition. This process, known as ashing, involves heating the sample to high temperatures in a controlled environment to oxidise the organic matter, leaving behind inorganic ash that can be analysed for its elemental content.
- Glass melting: Laboratory furnaces form glass into various shapes and sizes. This process involves heating the glass to high temperatures until it becomes malleable, at which point it can be shaped and cooled to form a solid.
- Materials testing: Laboratory furnaces are used to test the properties of materials under various temperature conditions. This can include testing a material’s strength, conductivity, or other characteristics to understand their behaviour under different conditions.
Key considerations to help you choose the right furnace
Once you’ve decided on the best lab furnace type for your process, it’s essential to think about the following factors and specifications:
- Temperature range: Make sure the furnace can reach the temperature range required for your specific application. Operating temperature ranges vary significantly across furnace models, from up to 1100°C for basic applications like drying, to furnaces above 1800°C used in advanced material research and metallurgy.
- Temperature uniformity: It’s vital to ensure the temperature within the furnace is evenly distributed, as variations can affect the accuracy and reliability of your results.
- Size and capacity: Consider the size of the furnace (including the internal chamber dimensions) with the size and volume of samples you need to process, as well as the available space in your lab.
- Heating elements: Different heating elements like Nickel-Chrome (NiCr) alloys and Silicon Carbide (SiC) impact performance and durability. For instance, NiCr alloys are suitable for lower temperatures and cost-effective applications.
- Heating rate: The heating rate determines how quickly the furnace can reach the desired temperature. A faster heating rate may be necessary for specific applications.
- Control system: The furnace should be easy to use and allow precise temperature control and monitoring. Take a look at our SNOL laboratory furnaces, which have Omron E5CC digital PID temperature controllers fitted as standard.
- Safety features: If necessary, look for furnaces with safety features such as over-temperature protection and explosion-proof construction. Some models are available with a lift door for enhanced safety, as it keeps the hot surfaces away from the operator.
- Compatibility with other equipment: Consider whether the furnace is compatible with any additional equipment or test instruments you may be using in your lab.
- Compliance with relevant quality, performance, and safety standards: Ensure your furnaces adhere to global standards required by laboratory applications. These cover aspects such as electrical safety, environmental compliance, and hazardous material handling. For example, if your furnace is to be sited in a lab that handles handling hazardous materials like chemicals, it must comply with ISO 14001.
- Maintenance and service: Look for a supplier that offers maintenance (see top tips below) and repair services and technical support to ensure your furnace is always in top working condition.
Top tips to help maintain your laboratory furnace
Taking a proactive approach to maintaining your laboratory furnace, prevents minor problems from escalating and helps keep it in top condition. Check out these top tips, so your furnace continues to operate accurately and efficiently:
- Inspect heating elements: Keep an eye on the heating elements, insulation, and thermocouples for any damage or degradation, and replace them when necessary. Ignoring them will affect uniform heat distribution and potentially cause the furnace to malfunction.
- Keep your calibration schedule up-to-date: This is a vital part of quality assurance, giving you the confidence your furnace is reaching and maintaining the correct temperature setpoints throughout its operating range. AML Instruments offer a UKAS-accredited laboratory oven and furnace calibration service to keep your laboratory running smoothly and equipment functioning at its best (there is an option for calibration to UKAS ISO 17025 and/or Nadcap AMS 2570 for those in the aerospace industry).
- Regular cleaning: Use appropriate solvents and brushes to keep the furnace and its components free of residue or build-up from previous processes. Never attempt to clean a hot furnace as it poses a severe burn risk — the furnace must be at ambient room temperature.
Find the right furnace for your lab
Our team is here to help you find the right furnace for your specific application. We also offer ongoing support to ensure your equipment is operating at its best, so you can process samples and materials with unerring precision.
Looking for a laboratory oven or forced air oven? We supply these too.
If you have any questions or queries, please get in touch.
