THE FABRICATION OF A PLUTONIUM HELIX FOR A DOPPLER EXPERIMENT. Work completed: September 1956

A helix constructed of plutonium was made to test the Doppler temperature effect in ZPR-III. The helix. 1 in. in diameter and 6 1/4 in. long. contained 240 g of deltaphase plutonium alloy encapsulated in titanium tubing. rour piutonium rods were extruded, joined together, and pushed into a titanium tube. This tube was swaged tightly over the piutonium rod. and the assembly was wound into a coil. Electrical leads to the coil were made by swaging copper tubing over the ends of the coil. The helix was tested by cycling about 500 times between 50 and 190 deg C. The coil was heated with a current of 130 amperes and cooled with a blast of chilled helium. Several helices of uranium were cycled during the same tests. Despite the severity of the thermal cycles. the helices were undamaged. (auth)