Melt metallurgy for non-ferrous foundries
Every casting is only as good and mechanically resilient as the internal structural properties allow. In order to always get the optimum results from the alloy used in the melting / holding process, HA offers a wide range of products for the melt treatment of all common non-ferrous metals (aluminium, magnesium, zinc, copper, lead).
Benefits
The products, also known as fluxes, are used to improve the melt properties by
- separating oxides from the liquid melt (reducing the amount of expensive metal lost in the dross)
- easing the removal of the, by then, dry dross
- cleaning the furnace and crucible walls, thus saving energy and reducing the risk of oxide inclusions
- achieving the desired hydrogen content
- improving the internal microstructure
Cleaning and drossing salts
HA has a wide portfolio of products that meet all of our customers’ requirements. They range from inexpensive salts that bind the oxides in the dross and separate them from the valuable aluminium, to special products for cleaning the furnace wall, to products adapted to specific alloys, which are free of sodium, fluoride or calcium, for example. The type of furnace and the degassing and melt cleaning method can also play a role in selecting the optimal product. Our experts for this product area would be delighted to support you in identifying the right product for your processes.
Special salts
These agents are designed to perform a range of functions, such as removing certain unwanted elements from the melt. Special salts include, for example, calcium removers for aluminium (also available sodium-free), magnesium removers for aluminium or aluminium removers for copper alloys.
This product category also includes cleaning and drossing salts developed for more exotic non-ferrous metals such as lead, zinc and copper alloys.
Degassing tablets
Molten aluminium can solve large quantities of hydrogen, which is easily absorbed from the air or via contact with moist objects (casting tools, crucibles, etc.). In its solid state, the hydrogen solubility is substantially lower. As a result, aluminium, when solidifying, excretes the hydrogen in the form of small bubbles – a bit like the process by which fizzy bubbles are released when a bottle of sparkling water is opened.
In order to reduce the hydrogen content in the molten aluminium, HA offers effective and easy-to-use degassing tablets that are plunged into the melt where they develop their full effect.
Grain refining and exothermic modification tablets
These easy-to-use tablets allow foundries to ensure that their castings achieve the desired microstructure later in the process.
A grain refinement, as the name indicates, leads to a smaller grain size during solidification, thus enhancing the mechanical properties.
Exothermic modification tablets are used to refine eutetic aluminium silicon alloys, improving their solidification morphology and at the same time their mechanical properties.
The modification only affects the Al-Si eutectic, which also benefits from the refinement: a considerable improvement of the strength and expansion values in sand and thick-walled gravity die casting
As an extended arm of the foundry, we offer you a comprehensive selection of consulting services in the field of metallurgy, including:
- analysing the metallurgical process
- optimising the metallurgical process
- developing and refining alloys
- analysing casting defects
- acting as an external Emissions Control Officer according to the German Federal Immission Control Act (BImSchG)
The HA Center of Competence offers a wide range of technical facilities. Our experienced foundry specialists support you in the material development of casting materials, casting of sample parts, alloy tests, standardised material samples (e.g. tensile tests, notched bar impact tests), tests with inoculation alloys and carburisation tests.