Zinc Aluminum AlloyCoated Steel

Resistance Welding

Lesson ObjectivesWhen you finish this lesson you will understand:•

Learning Activities1. View Slides; 2. Read Notes, 3. Listen to lecture4. Do on-line workbook

Keywords

Zinc Aluminum Alloy CoatingsApplied by Hot Dipping

Al = Durability in Industrial AtmospheresZn = Formability and galvanic protection

Galvalume 55% Aluminum, 1.5% Silicon, 43.5% ZincA250 = 0.50 oz/sq ft (0.8 mil thickness)A255 = 0.55 oz/sq ftA260 = 0.60 oz/sq ft

Galfan Type I: 5% Aluminum, 95% Zinc, misch metalType II: 5% Aluminum, 95% Zinc, 0.1%Mg

12 coating weights GF235 = 2.35 oz/sq ft, throughGF30 = 0.30 oz/sq ft

Typical Applications of Coated Steels

• Galvalume & Galfan -- Roofing & Siding -- Underbody Parts -- Exhaust Systems --Agricultural Equipment

Aluminum/ Aluminum Zinc Coating

• Need to brush oxide off surface• Higher currents needed• Reduced Electrode life

Zinc Aluminum AlloyConventional Galvanized

Galfan Galvalume

Wider Face4 to 5 times base metal thickness

Dispersion Strengthened Electrode preferred

AWS Welding Handbook

Weld Time (cycles)

Hot Dipped Galvanized

AWS Welding Handbook

Seam Welding

• Slightly Higher Currents• Lower Electrode Forces

AWS Welding Handbook

AWS Welding Handbook

Term Paper: Research Proposal