The voltage appears across the laser diode as a result of the current flowing through it. This parameter is defined as the light output intensity in the case that a specific current is applied to the device in the forward direction, and is typically expressed in units of W. This is shown on a graph as the. Even though no filler material is typically used for keyhole welding, the high temperatures of keyhole welding can vaporize volatile materials, producing a different composition in the fusion zone than in the base metal. Also, with hardenable steels, the rapid cooling generates fully martensitic. Amada Miyachi America, Inc.