4343/SA-7/7072Aluminum strip for B-tube and ratio-frequency welded tube
Aluminium strip for tubes
*Various specifications for B-TUBES, ratio-frequency welded tubes and other tubes
*Good surface condition and slitting precision
*Excellent collapse resistance during brazing
*Perfect corrosion resistance and long life
*Aluminium brazing material production
Complex assemblies can be turned into single unit by just one pass through a brazing furnace. Aluminium brazing facilitates the joining of parts with a near-eutectic Ai-Si filler alloy, the liquid temperature which is about 50 º C lower than that of the core. In serial heat exchanger production the filler alloy is supplied via a thin clad on a core alloy.
Compound Material
Aluminium brazing material is a sophisticated multi-layer compound consisting of a core alloy which provides the stength and life cycle requirements of the heat exchanger and a clad brazing filler. A one-sided protection layer can also be clad, in order to prevent water-side radiator corrosion.
During brazing, only the clad brazing alloy melts, while the core alloys remain solid. The design and the applied materials of the heat exchanger are adjusted to optimize the brazing result regarding the required post braze mechanical properties as well as the corrosion resistance.
Roll cladding
Today, two basic cladding techniques, roll bonding and cast cladding, have become established industrially. Roll cladding is a solid-state welding process, which is used to join similar and dissimilar aluminium alloys, and represents the primary method of manufacturing fuselage skin sheet for aircraft, bright products and brazing sheet for automotive applications. The cladding layers are attached to the core slab by welding and metallurgical bonding using hot rolling. The cast cladding technique is based on a conventional direct chill mould modified in order to allow multiple metal streams to be casted into one single ingot.
Cladding thickness
Signi's well established, roll bonding process guarantees tight cladding thickness tolerances, which are essential for ensuring stable brazing results. Rather thin clad layers of 5% can be manufactured, as well as brazing materials also with a cladding thickness of 20%.
1> Tolerance according to EN and ASTM.
2> Higher thickness on request.
3> Special dimensions, tolerances, and alloys on request.
The state-of-art slitting line also allows Signi Aluminium to meet the demand for ever-closer width tolerances for tube stock materials. Depending on the material thickness width tolerances from max. 0.05mm up to max 0.20mm can be ensured.
Clad Alloys
B-tube and ratio-frequency welded tube |
Alloy
|
Temper
|
Thickness
(mm)
|
Tolerance
(mm)
|
Clad rate(%)
|
Mechanical property
|
Tensile Strength
(MPa)
|
Yield
Strength
(MPa)
|
Elongation
Min.(%)
|
4343/SA-5/7072 |
H24 |
0.25~0.3 |
±0.008 |
8~12 |
160~210 |
≥120 |
5 |
4343/SA-7/7072 |
H24 |
0.25~0.3 |
±0.008 |
8~12 |
170~220 |
≥120 |
5 |
Glass mounting bracket material |
Alloy
|
Temper
|
Thickness
(mm)
|
Tolerance
(mm)
|
Clad rate(%)
|
Mechanical property
|
Tensile Strength
(MPa)
|
Yield
Strength
(MPa)
|
Elongation
Min.(%)
|
3003 |
H26 |
0.3~35 |
±0.015 |
None |
190~220 |
≥160 |
8 |
*4343 can be replaced by 4045/4047 etc, according to customer's requirement.
43434045\4047.
*Slitting tolerance can be controlled in ±0.02mm ±0.02mm.
*Alloy\specification and mechanical property can be customized according to different requirement. \. |