Spot Weld Mechanical Properties 3

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Spot Weld Mechanical Properties 3
Impact Testing
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Mechanical Properties 3

• Learning Activities
• View Slides
• Read Notes,
• Listen to lecture
• Do on-line workbook

• Lesson Objectives
• When you finish this lesson you will understand
• Impact Mechanical testing techniques
• Factors which effect performance in Impact tests
• The importance of these test for part design

Keywords Impact Test, Ductile-Brittle Transition,
Tensile Shear Impact Test, Direct Tension Impact
Test
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Mechanical Properties of Spot Welds

• Peel Tests
• Chisel Test
• Tensile Test
• Tensile Shear Ratios
• Torsion Test
• Impact Tests
• Fatigue Test

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Impact Testing of Tensile Shear Samples
Low Temp Ductile to Brittle Temp
Fine Evaluation of a new, Dua Phase.. SAE
Paper 780136, Fgeb 1978
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Effect of Sheet Size on Impact Test Results
Bibber, Spot Weldability of Low Carbon and other
Aircraft Steels, Welding Journal, Dec 1943
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Effect of Sheet Thickness on Impact
Results Tensile Shear Samples
Pollard, Spot Welding Characteristics of HSLA
Steel.., Weldign Journal, Aug 1974
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Effect of Nugget Size On Impact Test
Results Comparison of Test Samples
Direct Tension
Tensile Shear
Sawhill, Spot Weldabiloity of High Strength
Steels, Welding Journal, Jan 1980
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Effect of Weld Time (for same nugget diameter)
Increased weld time may have resulted in nugget
softening
Unger Behavior of Spot Welds Under
Impact Welding Journal, 1942
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Effect of Hold Time Plain Carbon Steel
No Effect on Tensile Shear
Slight Decrease In Impact Energy For Cross Tension
No Similar Data Found for Other Materials
Dinsdale A Comparison of Static and Impact
Strength Sheet Metal Industries, Aug 1977
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Effect of Chemistry
0.1 0.2 Carbon Steels
0.2 0.5 Carbon Steels
Hess Spot Welding of SAE Welding Journal, Oct
1943
Dinsdale A Comparison of Static and Impact
Strength Sheet Metal Industries, Aug 1977
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Effect of Chemistry - 40 ksi HSLA different
microalloy
Ti free Higher Impact Partial Nugget Failure
Higher Impact
Fine Spot Weldability of High Strength.. SAE
Paper 790005, Feb 1979
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Effect of Material Strength
Increase Strength
Bibber The Spot Weldability of Low
Carbon.. Welding Journal, Dec 1943