Aluminum Production and Properties

Resistance Welding Lesson Objectives

When you finish this lesson • you will understand:

Learning Activities

1. View Slides; 2. Read Notes, 3. Listen to lecture 4. Do on-line workbook

Keywords

Hall- Heroult Process Aluminum Cathode Carbon Anode Al Bauxite Alumina plus Fluoride salts Pxxyy xx = % Si Impurity yy = % Fe Impurity Additional Electrolytic Refining Available to get 99.999% Purity O CO 2 Typical Grade: P1020 0.10% Si & 0.20% Fe Grades Range From: P0202 to P1535

Facility for producing aluminum sheet re-rolled directly from molten aluminum Metals Handbook vol 2, ASM

AWS Welding Handbook

Chemical Composition of Aluminum Alloys [Reference: Resistance Welding Manual, p.11-2, RWMA]

Classification of Aluminum Alloys

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Heat-Treatable Alloys

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Can obtain increased strength levels through precipitation hardening Typical hardening additions include copper, magnesium, zinc and silicon These additions show increasing solid solubility with increasing temperature

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Alloys of this type include the 2000, 6000 and 7000 series Non-Heat-Treatable Alloys

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Strengthened by work hardening and solid solution strengthening

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Elements such as manganese, silicon, iron and magnesium are typical solid-solution hardening agents

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Alloys of this type include the 1000, 3000, 4000 and 5000 series

Some Applications of Aluminum Alloys •

Heat-Treatable Alloys

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2014 Hydraulic fittings for aircraft and automotive

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2036 6009 Automotive Body 2219 tanks 6061 Structural 6101 Electrical Conductors 7075 High Strength Aircraft Non-Heat-Treatable Alloys

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1060 Chem Processing Tanks 1100 Architectural 3003 General Purpose, Tanks 5052 Sheet Applications

Non-Heat Treatable Alloys Temper Designations Designation O F H1 H2 H3 Description Annealed, Recrystalized As Fabricated Strain Hardened Strain Hardened & Annealed Strain Hardened & Stabilized Application Lowest Strength, High ductility Fabrication with no special control over thermal or strain hardening Strain hardened without subsequent anneal Strain hardened more than the desired amount and then partially annealed to strength Strain hardened and low temp stabilization treatment to prevent age softening

Heat Treatable Alloys Temper Designations Designation O Description Annealed, Recrystalized As Fabricated Application Lowest Strength, High ductility F W T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 Solution Heat Treatment Fabrication with no special control over thermal or strain hardening Unstable temper application with subsequent period of natural age Cooled and naturally aged Cooled, cold worked & Naturally aged Solution heat treated, cold worked & naturally aged Solution heat treated & naturally aged Cooled and artificially aged Solution heat treated and Stabilized Solution heat treated, stabilized to provide special property Solution heat treated, cold worked, artificially aged Solution heat treated, artificially aged, then cold worked Cooled, cold worked, then artificially aged

For a more extensive description see the table in AWS Welding Handbook, Vol 3, 8 th Ed. Page 9

Employing These Various Treatments Can Produce Aluminum Alloys With A Wide Range of Mechanical Properties As Observed in The Following Tables

Mechanical Properties of Some Aluminum Alloys [Reference: Resistance Welding Manual, p.11-12, RWMA]

Mechanical Properties of Some Aluminum Alloys (CONT.) [Reference: Resistance Welding Manual, p.11-12, RWMA]

Effect of Temperature on Mechanical Properties of Aluminum Alloys [Reference: Resistance Welding Manual, p.11-13, RWMA]

Effect of Temperature on Mechanical Properties of Aluminum Alloys (CONT.) [Reference: Resistance Welding Manual, p.11-13, RWMA]

Effect of Temperature on Mechanical Properties of Aluminum Alloys (CONT.) [Reference: Resistance Welding Manual, p.11-14, RWMA]

Mechanical and Physical Properties of Some Automotive Alloys

[Reference: Guidelines to Resistance Spot Welding Aluminum Automotive Sheet, p.4, The Aluminum Association]