Roll Bond Sample Kit
Samples are for evaluation only and not material testing
1. Basic BiMetal Block
A perfect introduction to metallurgical bonds for those that have not been exposed to them before. Almost everyone will try to twist the stainless and aluminum layers apart. Good luck... The bond is stronger than the aluminum!
This sample has Spur's intert chromium interlay for the highest BiClad temperature resistance in the industry.
The top and bottom surfaces are as rolled, with deburred saw cut sides.
2. Bond Testing
How do we know the bond strength? The sample test coupon is part of a pull (tensile) test. The geometry is tightly controlled and the bond is placed at the joint between the aluminum and steel. When pulled, the aluminum will fail prior to the bond. After failure, aluminum can on top of the bond.
Other test methods include S-Bend, ultrasound, 90 degree bend and shear.
3. Aluminum Alloys
What kinds of aluminums can be bonded? Roll bonding gives precise control of bond parameters, which ultimately allows Spur to make difficult material combinations. 1050 is great for large structural transitions, but is very difficult to machine and not strong enough for thin shapes. 3003 is highly machinable but not very conductive. Spur is able to direct bond high strength 6061 without the need for a strength reducing high purity aluminum interlayer. We are also working on highly conductive, strong and machinable alloys such as 6063 and 6101. We also do some 4000 series.
This sample shows a heat spreader application with an easy to machine 6061 aluminum clad layer over 102 OFHC copper. The copper has a sanded finish which is applied after rolling.
4. Specialty Materials
What materials can be roll bonded? Lots of different metals can be rolled bonded. This sample shows grade 2 titanium direct bonded to 6061 aluminum. We can also do nickle, brass, bronze, copper, etc.. as the base metal. In almost all of Spur's products, aluminum is the clad material.
If we have not done the material combination before, we can try it pretty quickly.
5. Structural Bond
This sample shows thin A36 steel directly bonded to 6061 aluminum (with Cr interlayer). This makes for a much stronger bond than using a pure aluminum joining layer. The base metal can be much thicker, but the 1 inch of aluminum is our current limit (3003 is 3/4in). The bottom of the A36 shows the typical steel coloring as rolled.
Due to the thin steel and high temperature risks of welding (exceeding 350C), this sample is directly applicable to applications such as providing wear surfaces to aluminum in trucking, and cooktops with the steel replaced by stainless.
Multiple layers of metal can be joined with roll bonding. This sample shows 102 copper mounted to the top and bottom of high conductive 1050 aluminum. This sample is directly applicable to the power distribution / bus market.
We can roll multiple layers in one pass and sometimes make muliple rolls with each adding a layer.
7. Partial-Clad Overlay
With roll bonding, the clad and base metals do not have to be the same width or length. This sample shows a 1050 aluminum layer bonded to the top of the carbon steel, and is applicable to many markets. The steel is bluish from the heating process.
Overlay can only be accomplished when the base metal is harder and wider than the clad metal.
8. Partial-Clad Inlay
When the wider material is the softer clad layer, the harder base material will be rolled into the clad producing a partial-clad inlay bond.
This sample has 102 copper bonded to 1050 aluminum and is applicable to electrical and thermal applications.
9. Pipe and Tube Rings
Spur has a standard line of pipe and tube rings for joining aluminum to steel or stainless, with the sample being 3003 aluminum to 304L. The sample shows the typical water jet finish and is sized for standard pipes. Customers are encouraged to weld the aluminum side first to help conduct heat from the bond during welding.
10. Machine Blank
Pipe fittings and transitions are common for Spur. Unlike turning parts from round bar, with roll bonding the parts come from flat bars and must be cut into turnable blanks. For many machined parts, Spur starts with water jet cutting machine blanks which produces a good starting finish and does not heat the part, as would plasma or laser cutting.
The machine blank is 3003 bonded to 304L.
11. Tube Fitting
Machine blanks are turned into clad product. Spur has expertise in both milling and turning clad metal where location of bonds may be critical to the application. We have the equipment and experience to locate bond lines in cladded metal and to register from it during fabrication.
The sample shows a 3003 aluminum layer over 304L. Depending upon the pressures of the application, we recommend at least a .125 wall thickness with 3003 to 304L or 316L.
12. Thin Wall Turned Parts
Many pipe and fitting transitions applications are not only about changing materials, but also pipe sizes. The sample shows a complex thinwall shape in 3003 over 304L used in an HVAC application. The part is able to withstand 35 atm pressures, and temperature cycling from +200C to -100C.
13. Machined Stud
Spur can produce a wide range of weld studs that allow steel and stainless steel fastners to be used with aluminum plate. Simply weld the stud into the hole of the aluminum. A push nut version is shown, but other options may include features such as threads and grooves for clips.