conventional inert gas shield 104 as shown in fig1 the plasma gun 102 produces an ultrahigh temperature plasma plume 106 which is directed toward a suitable substrate 108 such as cooled steel stainless steel aluminum or titanium alloy substrate as shown in the cross sectional view of fig2 the plasma gun 102 has an axially aligned cathode 110 typically of a refractory metal with a low work function such as tungsten or thoriated tungsten and a water cooled anode 112 through which powdered metals to be vaporized and deposited on the substrate 108 may be introduced through appropriate passageways 114 116 if desired the thermal spray apparatus 100 fig1 may be enclosed in a controlled atmosphere chamber or vacuum chamber 118 if it is desired to exclude reactive gas such as oxygen or nitrogen and or to operate in subatmospheric pressure in operation an inert gas such as an argon helium mixture 103 which may include a small amount of hydrogen is introduced into the plasma gun 102 while direct current is applied from a suitable power source to the cathode and anode of the gun to heat the inert gas to a temperature of 10 30 thousand degrees kelvin to form a high velocity plasma plume 106 a selected amorphous metal alloy which is preferentially a bulk metal glass alloy having a largest dimension of about five microns or less is introduced into the plasma gun 102 through conventional introduction port 114 with an inert gas and or hydrogen the more volatile elements such as magnesium boron and aluminum can be in relatively larger particles while refractory elements such as zr are heat volatilized from a smaller particle form the metal.