Electric furnaces installed at national synchrotron facility

Diamond Light Source, the UK's national synchrotron facility in Oxfordshire, has taken delivery of seven Carbolite electric furnaces that provide researchers with a broad spectrum of high-quality thermal equipment for sample preparation and processing.

Diamond, the largest UK scientific investment for 40 years, is a third-generation light source with an electron beam energy of 3 Giga electron volts (three thousand million volts). At its heart is a circular vacuum chamber, half a kilometre in circumference, through which electrons travel at just below the speed of light. Passing the electrons through specially designed magnet arrays produces infra-red, ultra-violet and X-ray beams of exceptional quality and brightness, which enable researchers to study the basic structure of many materials, down to the scale of molecules and atoms.

Within the doughnut-shaped building are currently 14 experimental stations, known as beamlines, with eight more due for completion by 2012. The beamlines are supported by laboratories that provide researchers with comprehensive in-house facilities for performing cutting-edge experiments in a very wide range of fields, including health research, engineering, environmental science, sustainable energy, cultural heritage and fundamental physics. Plans for a further ten beamlines are currently under review.

Furnaces

Carbolite furnaces had previously been supplied for sample preparation and related activities at the Synchrotron Radiation Source (SRS) at Daresbury, Cheshire. The equipment supplied by the company to Diamond Light Source includes a specially designed high-vacuum tube furnace, four conventional tube furnaces and two chamber furnaces. Maximum operating temperatures are between 1200 and 1500degC. These furnaces are mainly used for heat treatments for inducing structural and phase changes, which is essential for material, engineering and environmental science. The tube furnaces enable additional species to be introduced or intercalated into the structure of materials, which can then be examined using X-ray diffraction.

The vacuum tube furnace has silicon carbide heating elements that provide a maximum operating temperature of 1500degC, with control provided by a Carbolite 301 PID controller that enables temperature ramp rates and dwell periods to be pre-set for different procedures. Samples are held in a work tube that is 50mm in diameter and 450mm long. Reliable vacuum performance on the model at DLS is achieved by means of a rotary vane roughing pump combined with a high-vacuum oil diffusion pump. Models with a turbo-molecular high-vacuum pump and fully oil-free roughing pump are also available from Carbolite.

DLS has four standard Carbolite tube furnaces that provide heating capabilities up to 1500degC in air or inert gases, and two of these feature three-zone control that enables temperature gradients to be applied or very accurate control to be achieved over long heated lengths. The two chamber furnaces have operating temperatures up to 1300degC and 1500degC, the higher-temperature model having a rapid-heating capability.