Tungsten Cathode Completed, En Route to FF-1February 27, 2015
The critical tungsten monolithic cathode, key to LPPFusion’s next set of experiments, has finally been completed and shipped. It arrived at Tungsten Heavy Powder headquarters in San Diego, California on Monday, Feb.23 from their manufacturing facilities in China. It is expected to arrive at LPPFusion’s Middlesex, NJ laboratory around March 2. “For a long time, this cathode has been in the future,” said LPPFusion Chief Scientist Eric Lerner,” and the future has finally arrived.” As described in the December LPP Focus Fusion report the great difficulty of manufacturing the part from pure tungsten to exacting requirements caused long delays, which have now ended.
After carefully testing and measuring the cathode, the LPPFusion team expect to install it in the FF-1 plasma focus device and begin experiments during March. The tungsten electrodes (the anode is already installed) are expected to totally stop vaporization of the electrode materials due to arcing, since they are each made of a single piece of metal, with no joins for arcs to form. In addition the tungsten material, which has the highest melting point and one of the highest boiling points of any material, is expected to eliminate additional vaporization from high energy (runaway) electrons during the earliest moments of the electrical discharge. Together, this should end the large amounts of impurities in the plasma, allowing the achievement of far higher fusion yields.
Preparations for the new experiments have continued, with a successful test of the new adjustors. With the aluminum model standing in for the tungsten cathode, Lerner, Chief Research Officer Hamid Yousefi and Consulting Engineer Anthony Ellis succeeded in using the micrometer adjustors to center the cathode on the anode to an accuracy of 25 microns (one thousandth of an inch). In addition, a new gantry has been purchased and will be installed to help handle the tungsten cathode, whose concentrated 35 kg mass makes it too difficult to lift and position manually.