United Technologies Corporation

Dennis C Stewart

Charles C McComas

John M Robertson

Enrique E Montero

Ronald R Cairo

Jack S Thrower

J Carter Barone

Donald R Cairo

Carter J Barone

The present invention relates to a process for joining two metal members together. The process comprises the steps of providing two parent metal members to be joined and a prealloyed interlayer foil having a melting point depressant; creating a joint interface by positioning the foil between two spaced apart surfaces of the two parent metal members to be joined together; applying a load substantially transverse to the joint interface which does not cause deformation of the surfaces; and applying localized rapid heating in the area of the joint interface at a temperature sufficient to effect bonding of the two metallic members while causing little or no degradation of microstructural or mechanical properties of the parent metal and a coarsening of grain size in rim portions of the metal members.

Process for bonding metallic members using localized rapid heating

A method is disclosed for controlling the magnitude and location of the weld notch which results from inertia welding of certain materials, such as superalloys. By controlling the size and geometry of the articles being joined a curved weld zone will result and the material expelled from the weld zone which produces the weld notch will be directed in a fashion which moves the weld notch outside of the original diameter of the articles being joined. The resultant welded article consisting of a larger portion and a smaller portion can be machined to the size of the smaller portion without any residual weld notch.

Inertia weld notch control through the use of differential wall

Methods of repairing defects in superalloy articles are described. Defective areas are cleaned and prepared to expose clean substrate surfaces. A layer of superalloy powder material containing a melt depressant (boron) is applied. A layer of superalloy material essentially free from boron is then applied. The dual coated article is heated to a temperature at which the boron containing layer melts, but the boron-free layer does not. The boron diffuses into the substrate raising the melting point of the molten material until solidification results. The unmelted surface layer is subsequently removed leaving behind a repaired article free from surface defects.

Repair of surface defects in superalloy articles

A method of improving the formability of sheet metal wherein the sheet metal is formed by die pins contacting spaced parts of the sheet with the properties of the sheet material itself determining the actual condition of curvature between the spaced parts contacted by the die pins. The sheet metal is perforated at the spaced part of the sheet contacting each die pin so that as each die pin is pressed into the sheet, each perforation expands and additional sheet material is supplied to the shoulder of the pin. Tops of the die pins can be modified with a boss to locate the perforations in the sheet metal and position it in respect to the die pins. Modified die pin tops can be formed with pointed inserts so that solid sheet metal can be used with the inserts piercing the sheet and the die pins then forming it. The sheet metal can also be partially formed and then perforated before the final forming.

Growing community of inventors

Palm City, FL, United States of America

Dennis C Stewart