Aluminium based master alloys
In the aluminium wrought and foundry alloy world, aluminium based master alloys are usually separated into different groups.
There are those added for composition adjustment to meet the final chemical specification. They are often added to strengthen the alloy and are therefore referred to as “hardeners”. Examples are AlMn, AlFe, AlCr, AlCu, AlV etc. either in the form of waffle ingot or as a powder compact, i.e. alloying tablets or briquettes.
Another important group is "grain refiners", alloys that are added for structure control. A grain refiner influences the aluminium alloy during the solidification stage. Its role is to prevent cracking, to combat shrinkage porosity and to increase the casting speed. Examples are Aluminium-Titanium-Boron or AlTiB for short. Sometimes also referred to by brand names such as Tibor or TiBAl. Another example is Aluminium-Titanium-Carbon or AlTiC for short, sometimes also called Ticar or TiCAl. These alloys are predominantly used in the form of coiled rod for continuous inoculation during casting. A rod feeding unit (rod feeder) ensures accurate addition rates.
For foundry alloys an important master alloy is the Aluminium-Strontium or AlSr "Modifier". Modifiers change the structure of the AlSi eutectic from a needle into a globular shape thereby markedly increasing alloy ductility. Strontium modification today has largely replaced previous Na-modification and is an essential part of modern melt treatment.
Finally some master alloys are added for specific purposes other than the ones listed above. For instance Aluminium-Boron or AlB or Boral is added to increase the electrical conductivity of EC grade aluminium, a procedure often referred to as boron treatment. Aluminium-Beryllium or AlBe and currently also Aluminium-Calcium (AlCa) is added to minimise oxide and spinel formation in AlMg alloys and for instance Aluminium-Zirconium is used to increase the recrystallisation temperature of the 7000 series alloys.
Copper based master alloys
In copper, brasses and bronzes one can make a similar subdivision into "hardeners", "grain refiners" and "special alloys". Copper-Manganese (CuMn), Copper-Aluminium (CuAl) and Copper-Iron (CuFe) are added for composition adjustment. Copper-Boron (CuB), Copper-Aluminium-Boron (CuAlB), Copper-Zirconium (CuZr), Copper-Titanium (CuTi) and to some extent Copper-Iron (CuFe) are used as a grain refiner for copper and certain brasses and bronzes. Copper-Magnesium (CuMg), Copper-Lithium (CuLi), Copper-Calcium (CuCa) and Copper-Phophorus (CuP, PCu) are proven deoxidisers. Finally, DHP deoxidised high phosphorous copper is used for decorative copper plating and as an undercoat in electroplating.
Zinc based master alloys
Perhaps less well known but no less important is our remarkable range of zinc master alloys such as Zinc-Titanium (ZnTi) used for strengthening wrought zinc alloys. Other alloys find their way into the galvanising industry with the aim of improving zinc coating properties.
KBM Affilips has developed many special, non-standard binary, ternary and complex alloys in close consultation with the end users. Worth mentioning is our capability to manufacture small batches (5-50 mt) of aluminium alloy rod for the production of aluminium welding rod and wire for special purposes such as flame spraying, sputtering and vapour deposition. An offshoot of our experience with boron containing alloys is the production of wear resistant aluminium composites.
We therefore encourage you to discuss your metallurgical requirements with us.