Abstract: A weld joint includes low and high alloy steel components. A weld bead between the low and high alloy steel components includes a first weld wire in contact with the low alloy steel component, a second weld wire in contact with the high alloy steel component, and a third weld wire between the first and second weld wires. The third weld wire has a higher percentage of chromium than the first weld wire and a lower percentage of chromium than the second weld wire. A method for welding includes applying a first weld wire to a low alloy steel component, applying a second weld wire to a high alloy steel component, and applying a third weld wire between the first and second weld wires. The third weld wire has a higher percentage of chromium than the first weld wire and a lower percentage of chromium than the second weld wire.

Abstract: Embodiments of the invention relate generally to welding methods and, more particularly, to methods for welding in a horizontal position and a joint structure suitable for such methods. In one embodiment, the invention provides a method of forming a welded joint between two components, the method comprising: aligning a first and second component to form a joint therebetween, the joint comprising: a protrusion of the first component, and a recess of the second component, wherein the protrusion and recess have complimentary shapes; orienting the first and second components such that a major axis of each is oriented vertically; and welding the first and second components at a substantially horizontally-oriented root opening, the substantially horizontally-oriented root opening positioned along the joint.

Abstract: Heat treatment processes for hardening a workpiece such as a turbine blade include attaching a spacer to a workpiece surface, wherein the spacer comprises an inner profile mirroring the workpiece surface and an outer profile effective to generally uniformly distribute heat to the workpiece surface, heating the spacer to uniformly heat the workpiece surface at a temperature effective to form an austenitic microstructure in the workpiece surface, cooling the workpiece surface at a rate effective to transform the austenitic microstructure to a martensitic microstructure, and removing the spacer from the workpiece prior to or subsequent to cooling.

Abstract: In one embodiment, a system includes a welding controller configured to receive images from multiple observation points directed toward a deposition zone. The welding controller is also configured to control a parameter affecting deposition based on a differential analysis of the images.

Abstract: Heat treatment processes for hardening a workpiece such as a turbine blade include attaching a spacer to a workpiece surface, wherein the spacer comprises an inner profile mirroring the workpiece surface and an outer profile effective to generally uniformly distribute heat to the workpiece surface, heating the spacer to uniformly heat the workpiece surface at a temperature effective to form an austenitic microstructure in the workpiece surface, cooling the workpiece surface at a rate effective to transform the austenitic microstructure to a martensitic microstructure, and removing the spacer from the workpiece prior to or subsequent to cooling.