Hybrid butt-lap joint, and method of production

This opportunity has now closed and is no longer accepting expressions of interest.

The Business Opportunity

Natural Resources Canada (NRCan) is seeking expressions of interest from firms wishing to enter into a commercial licensing arrangement to bring to market our patented “Hybrid butt-lap joint, and method of production”, which was developed by researchers at our CanmetMATERIALS Hamilton laboratory. The ideal licensee would be a distributor for this technology, and would have the capacity for the manufacturing, service, maintenance, support, marketing and sales. The ideal licensee will manufacture braze-welding materials that can be used in the automotive sector or other industry that manufacture components comprising aluminum-steel parts.

Brief Technology Description

NRCan has filed a Patent Cooperation Treaty (PCT) application for this technology, disclosing lap joints and butt joints that can be used in braze-welding metals, especially metallic sheet materials. The invention relates to hybrid joints that include features of lap joints and butt joints, which are suitable for joining articles and parts, especially sheets, composed of different metals including aluminum and steel. Also disclosed are methods of joining such hybrid joints.

Reference Material

• Patents: PCT/CA2020/051470, published as WO2021/081661
• Appendix A: Technology Background and Details
• Appendix B: Business Plan Required Format

Expression of Interest

Companies interested in commercializing the NRCan technology must submit a letter of interest to NRCan on or before February 28, 2022. Preference will be given to Canadian companies, but U.S. and other foreign companies will also be considered provided that such foreign companies demonstrate a benefit to Canada.

NRCan will invite qualified companies to attend an interactive webinar where additional technical information will be presented. Participation in this information session will be subject to signing a non-disclosure agreement. Following the webinar, companies may submit questions and requests for clarifications. NRCan’s responses to questions and requests for clarifications will be issued to all qualified companies alike.

Companies interested in becoming NRCan’s licensee will then be required to submit a business plan for NRCan’s consideration.  Business plans must address all of the elements outlined in Appendix B: Business Plan Required Format, and must be submitted to the contact below.

Contact

Maria de Fatima Machado
Intellectual Property Officer - Intellectual Property Division (IPD)
Natural Resources Canada/Government of Canada
maria.machado@nrcan-rncan.gc.ca
P: 343-572-0389

Appendix A: Technology Background and Details

Background

Welding and joining techniques sometimes require secure joining of different metals. In production and industry it is often desired to weld aluminum to steel or vice versa. Steel sheets and components have relatively high strength, but higher weight compared to corresponding aluminum sheets and components. For this reason, aluminum sheets and components are increasingly used, for example, in the car manufacturing industry, in view of their lower density and lightness relative to similar steel components.

A butt weld is one of the simplest and versatile types of weld joint designs. The joint is simply formed by placing two pieces of metal end-to-end and then welding along the join. Butt joints can be welded using arc welding and high energy beam welding.

Various welding techniques may be employed to achieve such welded joints, the choice of which depends upon the components being welded. Braze-welding (also often called brazing-welding), for example, is known for joining aluminum and steel sheets together. Filler materials and fed wires may also be used to supply molten material to help bond the metals together.

Braze-welded butt-joints made by the techniques of the prior art can present some challenges.  When producing an aluminum / steel butt-joint from one side, the welding parameter window may be relatively small and may be difficult to control. lf the heat input is too great, the heat may burn through the aluminum sheet, whereas if the heat input is too small then it may be insufficient to produce the braze-welding on the side of the butt joint opposite the welding energy.

Consequently, there is a need in the art for an improved connection between aluminum and steel components and sheets, in an end-to-end or an edge-to-edge configuration. There is also a need for improved techniques that give rise to stronger braze-welded joints between different metals, particularly under multiaxial loading conditions.

Hybrid Butt-Lap Joint, and Method of Production

In order to solve these issues, NRCan is offering a hybrid butt-lap joint and method for producing a hybrid butt-lap braze-welded joint between a steel workpiece, such as a steel sheet, and an aluminum workpiece.

The hybrid butt-lap joint comprises:

1. a portion of a steel workpiece, such as a steel sheet, and a portion of an aluminum workpiece, such as an aluminum sheet, with edges positioned in near contact with one another to provide a steel / aluminum butt region;
2. a second aluminum sheet across the steel / aluminum butt region flush with one face of the steel sheet and one face of the aluminum sheet, so that the second aluminum sheet overlaps in contact or near contact with both the steel sheet and aluminum sheet on one side thereof;
3. solidified weld filler material extending across the steel / aluminum butt region to provide a butt joint, and between at least the second aluminum sheet and the steel sheet to provide a lap-joint therebetween;
4. optionally a solidified, previously melted, filler alloy foil or powder positioned between the second aluminum sheet and either or both of the steel sheet and the aluminum sheet;
5. optionally solidified weld metal between the second aluminum sheet and the steel sheet; with the second aluminum sheet at least partially brazed to the steel sheet.

The method for producing a hybrid butt-lap braze-welded joint comprises the steps of:

1. positioning the steel sheet and the aluminum sheet for edge-to-edge contact or near contact with one another, thereby to provide a steel / aluminum butt region between an edge of the steel sheet and an edge of the aluminum sheet;
2. positioning a second aluminum sheet flush across the steel / aluminum butt region on one side of the steel and aluminum sheets, so that the second aluminum sheet overlaps in contact or near contact both with a portion of one face of the steel sheet and a portion of one face of the aluminum sheet adjacent the steel / aluminum butt region;
3. braze-welding along the steel / aluminum butt region, on a side of the steel and aluminum sheets opposite the second aluminum sheet; and
4. optionally welding on a same side of the steel and aluminum sheets as the second aluminum sheet, to lap braze-weld the second aluminum sheet and the steel sheet together.

Appendix B: Business Plan Required Format

Companies are encouraged to submit concise and clear evidence under the following headings:

Executive Summary

Section 1: Company Information

• General overview and company summary
  • Organizational maturity
  • Experience /success in the industry
  • Technical capability
  • Marketing capacity
• Corporate objectives
  • Short-term objectives
  • Long-term objectives

Section 2: Key Personnel and Networks

• Provide company organization chart identifying key members and foreseen roles
• Provide resumes of personnel key to this project including credentials and relevant experience

Section 3: Knowledge and Experience

• Previous experience on similar projects
• Experience testing welding
• Experience conducting business in welding industry
• Knowledge of the regulatory structure for welding used in the automotive sector or other industry that manufacture components comprising aluminum-steel parts
• Provide evidence of Quality Managed System

Section 4: Financial Stability

Each company authorises NRCan to make credit enquiries about it and any of its affiliates and to receive and exchange credit information from credit reporting agencies or other persons with which the company or any of its affiliates has or may expect to have financial dealings. Each company must provide NRCan with the company’s (and, on request by NRCan, any of the company’s affiliates) audited financial statements for the last three financial years for which they are available and financial statements for any period after the last audited period.

Section 5: Market, Customer, and Competition Analysis

• Market opportunity, size and trends
• Key customer bases
• Key competitors

Section 6: Production and Marketing Plan

• Product or services description
• Distribution channel(s)
• Target markets (i.e. Canada, USA, worldwide) and sales strategy

Section 7: Company Financial Information

• Five-year cash flow forecast
• Capital cost estimates
• Operating budgets
• Proposed sale price for product (s) or services incorporating NRCan’s technology
• Proposed profit margin targets for sales of product(s) or services incorporating NRCan’s technology
• Proposed royalty structure for product (s) or services incorporating NRCan’s technology