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Clad Materials. Resistance Welding . Learning Activities View Slides; Read Notes, Listen to lecture Do on-line workbook. Lesson Objectives When you finish this lesson you will understand:. Keywords. Steel - Aluminum Cladding. Rolling a. Cold b. 600-750 F. Cleaning.
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Resistance Welding • Learning Activities • View Slides; • Read Notes, • Listen to lecture • Do on-line workbook • Lesson Objectives • When you finish this lesson you will understand: Keywords
Steel - Aluminum Cladding Rolling a. Cold b. 600-750 F Cleaning Post-Heating ~ 1000F
Hansen, Const of Binary Alloys McGraw-Hill, 1958
FeAl3, Fe2Al5 (Brittle) Steel Si > 0.25% in Steel Tends to Reduce Brittle Iron-Alumindes Thus Higher Post Roll Temperatures can be employed Aluminum Steel Steel Aluminum Steel Aluminum Steel
Fe-Al Clad Material Oikawa et al, RSW of Steel & Al Sheet Using Insert, Science & Tech of Welding & Joining, vol4, 1999
Heat Flow in Spot Welding (Fe - Al) The lower MP of Aluminum Causes Rapid Nugget Growth Which Can Lead to Al Expulsion A Larger Electrode on the Al Side Might Help Steel Aluminum Fe Al Fe Al
Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Steel Aluminum Fe-Al Weld
Fe-Fe/Al-Al Fe-Al IMC = Fe2Al5 Oikawa et al, RSW of Steel & Al Sheet Using Insert, Science & Tech of Welding & Joining, vol4, 1999
Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Fracture Occurred on Tensile Load At the IMC Interface With Thinner Aluminum Sheet, Fracture Occurred by Nugget Pull-out Oikawa et al, RSW of Steel & Al Sheet Using Insert, Science & Tech of Welding & Joining, vol4, 1999
Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Heat Flow in Spot Welding (Fe - Trans - Al) Steel Steel Aluminum Aluminum
Steel Steel Aluminum Transition Aluminum Fe-Fe/Al-Al Weld Oikawa et al, RSW of Steel & Al Sheet Using Insert, Science & Tech of Welding & Joining, vol4, 1999
Weld With 2 mm Steel Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Shrinkage Voids in Al Due to Faster Cooling 1 MM Thick Steel (Faster Cooling) Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Oikawa et al, RSW of Steel & Al Sheet Using Insert, Science & Tech of Welding & Joining, vol4, 1999
Chang et al, Spot Welding Al to Steel, Practical Welding Today, May/June 1999
Aluminum - Titanium Aluminum Titanium
Ti-Ti Welds Aluminum High Conductivity Low Resistivity Low MP Titanium Low Conductivity High Resistivity High MP Ti melts, Heat flows to Al (melts a little because lower MP) but because of High Al Conductivity, Heat conducted to Electrodes
Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Ti-Al Welds Electrode Indented Forcing Al Expulsion Ti Al Ti Al The high MP & high Resistance Ti pushes heat into the Aluminum Causing melting and expulsion along the Interface
Ti Al Ti Al Ti to Al Weld Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
No Current Range Expulsion Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Oxide film between Al & Ti prevents interdiffusion This also promotes Interfacial Failure Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Case 1 Electrode Free to Move Case 2 Electrode Restrained Al-Al Welds
Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
No Restraint With Restraint Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Watanabe, Resistance Welding of Ti/Al clad plate, Welding International, May 1996
Stainless Steel Clad Aluminum & Copper Hot Rolled Aluminum Stainless Steel Stainless Steel Copper