Alloys
Billet
As the raw entry material we use aluminium billets, diameter ø 152, ø 178, ø 203, ø 254 and ø 305mm cast out of primary aluminium, alloy, family 6000, of a guaranted chemical composition.
Production cycle of pressing
Production cycle of pressing can be divided into several phases that occurs on different machines, and they all together constitute a single press line.
Warming furnace
Inside of furnace for warming up of billets is coated with a special material produced and designed to maintain interior temperature and insulate interior from the outward surroundings. Furnace is divided into several zones, each of which can be programmed to different temperatures. The accuracy of temperature adjusting, by zones, is controlled with thermo pairs that periodically control the adjusted temperatures and compare them to the set temperatures at pressing out.Cutting of billets
In preparation of billets for pressing, so called hot shear is used, due to its numerous advantages in relation to the traditional billet cutting off systems: - shorter time of cutting, 25 – 35 seconds, in relation to two minutes with the common way of cutting, no waste at sawing; - better usage of material, since it is possible to make various adjustments of cutting lengths, which is especially relevant at the unplanned tool changes. With usage of this system the entire billet length is used.
Tools
Profile appearance depends on the tool trough which it is pressed, and in the factories of Feal group exist over 9000 various tools. During pressing tools can be cooled with liquid nitrogen that results with a higher speed of pressing, better surface appearance and extending of tool life.
Types of alloys
The type of alloy and method of heat treatment after pressing determines the mechanical properties of profiles. In the following charts some alloys are shown with its chemical composition and mechanical properties after pressing. The quality of alloy’s chemical composition is guaranteed by the manufacturer.Aluminium alloy 6060, is the most frequently used alloy because of good mechanical properties and suitability for extrusion.
Chemical composition
- Si: 0.30÷060
- Fe: 0.10÷0.30
- Cu: 0.10
- Mn: 0.10
- Mg: 0.35÷0.60
- Cr: 0.05
- Ni: –
- Zn: 0.15
- Ti: 0.10
- ostali: –
- Al: ostatak
Mechanical properties
- Rp0.2 (N/mm2) 150÷160
- Rm (N/mm2) 190÷215
- A (%) 6
Aluminium alloy 6063, often called the “architectural alloy” is also used to create profiles for the construction of facilities because of suitability for heat treatment and anodisation.
Chemical composition
- Si: 0.20 ÷ 060
- Fe: 0.35
- Cu: 0.10
- Mn: 0.10
- Mg: 0.45 ÷ 0.90
- Cr: 0.10
- Ni: –
- Zn: 0.10
- Ti: 0.10
- ostali: –
- Al: ostatak
Mechanical properties
- Rp0.2 (N/mm2) 180÷200
- Rm (N/mm2) 225÷245
- A (%) 6
Aluminium alloy 6005A is a medium strong, heat treatable alloy, with excellent corrosion resistance and is used to create a profile that requires greater tensile strength, than for the previous two alloys.
Chemical composition
- Si: 0.50÷0.90
- Fe: 0.35
- Cu: 0.30
- Mn: 0.50
- Mg: 0.40÷0.70
- Cr: 0.30
- Ni: –
- Zn: 0.20
- Ti: 0.10
- Mn+Cr: 0.12÷0.50
- Al: ostatak
Mechanical properties
- Rp0.2 (N/mm2) 200÷225
- Rm (N/mm2) 250÷270
- A (%) 6
Aluminium alloy 6082, as well as all alloys from the group 6000, are characterized by good thermal processing, resistance to corrosion and with the highest tensile strength of this group of alloys.
Chemical composition
- Si: 0.70÷1.30
- Fe: 0.50
- Cu: 0.10
- Mn: 0.40
- Mg: 0.60÷1.20
- Cr: 0.25
- Ni: –
- Zn: 0.20
- Ti: 0.10
- Ostali: –
- Al: ostatak
Mechanical properties
- Rp0.2 (N/mm2) 250÷260
- Rm (N/mm2) 290÷310
- A (%) 6
