US Patent 10024166 Turbocharger shaft and wheel assembly

A unit for a turbocharger can include a turbine wheel portion that includes a turbine wheel material and a turbine wheel axis; a shaft portion that includes a shaft material and a shaft axis where the shaft material includes a molybdenum content less than 0.5 percent by weight; and a weld that includes a nail shape in cross-section where a head portion of the nail shape includes an axial dimension of approximately 1 mm or less and wherein a shank portion of the nail shape includes an axial dimension of approximately 0.4 mm or less.