onia ▁Category : National ization <0x0A> </s> ▁Electron - be am ▁w eld ing ▁( EB W ) ▁is ▁a ▁fusion ▁w eld ing ▁process ▁in ▁which ▁a ▁beam ▁of ▁high - vel ocity ▁electrons ▁is ▁applied ▁to ▁two ▁materials ▁to ▁be ▁joined . ▁The ▁work pie ces ▁m elt ▁and ▁flow ▁together ▁as ▁the ▁kin etic ▁energy ▁of ▁the ▁electrons ▁is ▁transformed ▁into ▁heat ▁upon ▁impact . ▁E B W ▁is ▁often ▁performed ▁under ▁vac u um ▁conditions ▁to ▁prevent ▁diss ip ation ▁of ▁the ▁electron ▁beam . ▁ ▁History ▁▁ ▁Electron - be am ▁w eld ing ▁was ▁developed ▁by ▁the ▁German ▁phys ic ist ▁Karl - He in z ▁Ste iger wald ▁in ▁ 1 9 4 9 , ▁who ▁was ▁at ▁the ▁time ▁working ▁on ▁various ▁electron - be am ▁applications . ▁Ste iger wald ▁conce ived ▁and ▁developed ▁the ▁first ▁practical ▁electron - be am ▁w eld ing ▁machine , ▁which ▁began ▁operation ▁in ▁ 1 9 5 8 . ▁ ▁American ▁invent or ▁James ▁T . ▁Russell ▁has ▁also ▁been ▁cred ited ▁with ▁design ing ▁and ▁building ▁the ▁first ▁electron - be am ▁wel der . ▁ ▁Physics ▁of ▁electron - be am ▁he ating ▁Elect rons ▁are ▁elementary ▁particles ▁possess ing ▁a ▁mass ▁m ▁= ▁ 9 . 1   ·   1 0 − 3 1   kg ▁and ▁a ▁negative ▁elect rical ▁charge ▁e ▁= ▁ 1 . 6   ·   1 0 − 1 9   C . ▁They ▁exist ▁either ▁bound