US-20260124695-A1 - METAL-CORED WIRE ELECTRODE FOR HIGH DEPOSITION RATE WELDING PROCESSES

US20260124695A1US 20260124695 A1US20260124695 A1US 20260124695A1US-20260124695-A1

Abstract

The present disclosure relates generally to an improved design of a metal-cored welding wire electrode for use on a high deposition rate welding process that resistively preheats the wire prior to being subjected to the welding current. The preheat circuit reduces the welding current drawn by the electrode so that higher wire feed speeds, and thus higher deposition rates, may be obtained. The metal-cored welding wire includes both a higher fill rate (a greater percentage of the welding wire is the granular core) along with added sulfur and an added bead wetting agent. The bead wetting agent may be one or more of selenium, tellurium, arsenic, gallium, bismuth, and tin. The improved metal-cored welding wire leads to an enhanced weld deposit appearance that means the weld deposits are less likely to be rejected as unusable.

Inventors

Joseph C. Bundy
Steven E. Barhorst
Sindhu H. Thomas
Mario A. Amata

Assignees

HOBART BROTHERS LLC

Dates

Publication Date: 20260507
Application Date: 20250616

Claims (2)

1 - 20 . (canceled)
21 . A metal-cored welding wire electrode for high deposition rate welding comprising: a metallic sheath encapsulating a granular core, wherein the granular core comprises between 20 and 30 wt. % of the metal-cored welding wire electrode; wherein the metal-cored welding wire electrode comprises, by weight of the metal-cored welding wire electrode: 0.01 to 0.03 wt. % sulfur, 0 to 0.12 wt. % carbon, 0.06 to 0.09 wt. % of a bead wetting agent, and 0 to 1 wt. % nickel; and wherein the bead wetting agent consists of one or more of selenium, tellurium, arsenic, gallium, bismuth, and tin.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims benefit of priority to U.S. provisional patent application No. 63/046,349, entitled “METAL-CORED WIRE ELECTRODE FOR HIGH DEPOSITION RATE WELDING PROCESSES”, filed Jun. 30, 2020, the contents of which are herein incorporated by reference in their entirety. BACKGROUND Arc welding is commonly used in numerous applications such as shipbuilding, offshore platform, construction, heavy equipment, pipe mills, and so forth. Certain arc welding processes (e.g., Gas Metal Arc Welding (GMAW) and Metal-cored Arc Welding (MCAW)) utilize welding wire, which generally provides a supply of filler metal for the weld deposit and provides a path for current during the arc welding process. Tubular welding wire, for example, includes a metallic sheath encircling a granular core. In particular, metal-cored welding wires are a type of tubular welding wire that generally produce a substantially slag-free weld deposit, which reduces post-weld processing compared to other types of tubular welding wire, such as flux-cored tubular welding wires. Gas metal arc welding (GMAW) is an electric arc welding process using an arc between a continuous filler metal electrode and the weld pool with externally supplied shielding gas. Certain efforts to increase deposition rate include feeding multiple wires into a weld pool, running multiple arcs into a weld pool, and running a hybrid laser/GMAW process. Multiple arc processes are difficult to manage due to limited access to the weld joint and electromagnetic interactions. Higher deposition rates are restricted because weld bead profiles become convex and the weld surface becomes less appealing as the heat input required to burn off welding consumables increases. At welding currents over approximately 400 amps, the weld surface tends to become heavily oxidized, more convex with less useful weld metal, and has unattractive, coarse freeze lines. Thus, there exists a need for improved design of a metal-cored welding wire electrode for use on a high deposition rate welding process that resistively preheats the wire prior to being subjected to the welding current. The metal-cored welding wire of the present disclosure uses multiple surface active elements to perform two key functions. First, the components modify the surface tension so that the weld metal flows easily and smoothly into the base metal allowing for faster travel speeds to be achieved. These components also modify the flow characteristics of the silicate islands that form and pull them away from the weld toe lines allowing for better wetting and easy removal. Second, the metal-cored wire uses a higher level of fill, reducing the wall thickness. This, in turn, reduces the welding amperage drawn to burn off the wire at a given wire feed rate. Because of the lower welding amperage, the thinner walled metal-cored electrode can use a higher wire feed rate in order to deposit even more weld metal yet stay below a critical amperage where undesirable weld appearance (“cooked” appearance) occurs. BRIEF DESCRIPTION In an embodiment, a metal-cored welding wire includes a metallic sheath encapsulating a granular core, wherein the granular core comprises between 20 and 30 wt. % of the metal-cored welding wire electrode. The metal-cored welding wire electrode includes, by weight of the metal-cored welding wire electrode: 0.01 to 0.03 wt. % sulfur, 0 to 0.12 wt. % carbon, 0.01 to 0.15 wt. % of a bead wetting agent, and 0 to 1 wt. % nickel. The bead wetting agent may be one or more of selenium, tellurium, arsenic, gallium, bismuth, and tin. In another embodiment, a method for high deposition rate welding includes resistively preheating a metal-cored welding wire electrode comprising a metallic sheath encapsulating a granulated core, establishing an arc between the metal-cored welding wire electrode and a workpiece, and melting at least a portion of the metal-cored welding wire electrode and at least a portion of the workpiece using the heat of the arc to form a weld deposit. The metal-cored welding wire electrode includes, by weight of the metal-cored welding wire electrode: 0.01 to 0.03 wt. % sulfur, 0 to 0.12 wt. % carbon, 0.01 to 0.15 wt. % of a bead wetting agent, and 0 to 1 wt. % nickel. The bead wetting agent may be one or more of selenium, tellurium, arsenic, gallium, bismuth, and tin. It is to be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter