Method for welding depending on a preferred direction of the substrate

摘要

Welding repairs are often carried out on directionally solidified components that nevertheless do not possess the desired crystallographic surface alignment, which reduces mechanical strength. The method provided selects the direction of travel depending on the crystallographically preferred direction of the substrate such that no more misorientations occur. A laser beam may be used for remelting.

主权项

1. A method for welding a directionally solidified component, comprising:
moving an energy source or a substrate with respect to the other of the energy source or the substrate along a direction of movement, wherein the substrate comprises grains solidified in a columnar form or a single-crystal form; melting the substrate with the energy source to form a melt along the direction of movement, wherein the melting produces a solidification front between the melt and a solidified region of a melt, and wherein the melt includes a temperature gradient on the solidification front; defining a first angle between a first preferred crystallographic direction of dendritic growth of the substrate and the temperature gradient on the solidification front; defining a second angle between the temperature gradient and a second preferred crystallographic direction of dendritic growth on the solidification front; and resolidifying the melted substrate directionally in the columnar form or the single-crystal form in the second preferred crystallographic direction of dendritic growth of the substrate; wherein the direction of movement of the substrate or the energy source is selected such that the second preferred crystallographic direction of dendritic growth is directed parallel to a surface of the substrate.