Clad Materials

1
Clad Materials
2
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
3
Steel - Aluminum Cladding
Rolling a. Cold b. 600-750 F
Cleaning
Post-Heating 1000F
4
Hansen, Const of Binary Alloys McGraw-Hill, 1958
5
FeAl3, Fe2Al5
(Brittle)
Steel
Si gt 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
6
Fe-Al Clad Material
Oikawa et al, RSW of Steel Al Sheet Using
Insert, Science Tech of Welding Joining,
vol4, 1999
7
Table of Steel and Aluminum Properties
8
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
9
Chang et al, Spot Welding Al to Steel, Practical
Welding Today, May/June 1999
10
Steel
Aluminum
Fe-Al Weld
11
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
12
Chang et al, Spot Welding Al to Steel, Practical
Welding Today, May/June 1999
13
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
14
Chang et al, Spot Welding Al to Steel, Practical
Welding Today, May/June 1999
15
Heat Flow in Spot Welding (Fe - Trans - Al)
Steel
Steel
Aluminum
Aluminum
16
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
17
Weld With 2 mm Steel
Chang et al, Spot Welding Al to Steel, Practical
Welding Today, May/June 1999
18
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
19
Oikawa et al, RSW of Steel Al Sheet Using
Insert, Science Tech of Welding Joining,
vol4, 1999
20
Chang et al, Spot Welding Al to Steel, Practical
Welding Today, May/June 1999
21
Aluminum - Titanium
Aluminum
Titanium
22
Properties of Ti Al
23
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
24
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
25
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
26
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
27
Ti
Al
Ti
Al
Ti to Al Weld
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
28
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
29
No Current Range Expulsion
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
30
Oxide film between Al Ti prevents
interdiffusion
This also promotes Interfacial Failure
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
31
Case 1 Electrode Free to Move
Case 2 Electrode Restrained
Al-Al Welds
32
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
33
No Restraint
With Restraint
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
34
Watanabe, Resistance Welding of Ti/Al clad
plate, Welding International, May 1996
35
(No Transcript)
36
(No Transcript)
37
(No Transcript)
38
(No Transcript)
39
(No Transcript)
40
Stainless Steel Clad Aluminum Copper
Hot Rolled
Aluminum
Stainless Steel
Stainless Steel
Copper