Vacuum Metallizing - VM Grade Tungsten Strand
VM grade tungsten wire, used in VM strand, is made by controlled processing techniques starting from the ore and continuing through doping and wiredrawing. Highly purified tungsten oxide, which has been reduced to tungsten powder in pure hydrogen, is pressed into bars, sintered, and worked into wire. The wire, drawn to size, is cleaned and stranded in various combinations as desired. As a result, our high-purity doped strand is produced to provide a uniform and controlled recrystallization rate important in the vacuum-metallizing process. The techniques allow achievement of a high number of flashes per coil by eliminating premature coil brittleness, distortion, and sag, the major causes of failure during reloading and processing.
Furnace Elements - Molybdenum Strand
Molybdenum strand or cable is often used in place of single wire molybdenum for furnace element windings. Its purpose is to obtain an equivalent current carrier with the higher degree of ductility required in some muffle shapes. Also, higher watt loading per unit length can be achieved by virtue of the increased surface, leading to equivalent power dissipation at lower element temperature and therefore to longer furnace life and more uniform temperature distribution. Because of molybdenum's inherent ductility, strands from larger wire sizes are available.