High Quality Metal for Making Aluminum Castings
To create aluminum castings, molten aluminum is poured into a mold. Depending on the situation, sometimes a vacuum is applied. The result is permanent mold castings being made stronger compared to sand or die castings. At Offshore Direct Metals, we work with the best suppliers of metals in the world. For the customer, this equates to an overall cost savings but without compromising on the quality of the final product.
The primary reasons this company’s aluminum castings are of such high quality is the material itself but also the process involved. Of all metallic elements in the world, aluminum is the one in most abundant. This particular material occurs as a compound. A few examples of the minerals that make up aluminum include turquoise, corundum, cryolite, bauxite, spinel, alunite, diaspora, and various silicates.
Using special chemical processing, impurities from the bauxite are removed, which results in the making of aluminum oxide. Bauxite is then crushed and blended in with a sodium hydroxide solution, followed by being heated so alumina is dissolved. Through settling and then filtration, more impurities are eliminated.
Once the solution has cooled, it is agitated whereby hydrated alumina crystals form. Once the crystals are washed and thoroughly dried, alumina, otherwise referred to as aluminum oxide is left. On average, it takes about four pounds of bauxite to make two pounds of alumina. Aluminum is made when a solution of alumina is electrolyzed in molten fluorides. Based on the overall process, the final aluminum is of high quality. For one pound of aluminum, two pounds of alumina are processed.
To make aluminum castings, either a primary or secondary log is used. The primary log is pure aluminum while the secondary consists of both prime and scrap. To make secondary aluminum, prime, scrap, and hardeners are used when charging the furnace. At Offshore Direct Metals, aluminum castings always comply with strict industry standards.
For example, prime aluminum must be 99.8% pure and come in a T-bar, pig, or tub sow. In addition, the iron content is used to categorize prime. As far as scrap for secondary aluminum, this comes from outside sources and for hardeners, these are different elements added to the bath process in order to strengthen aluminum but also provide the final product with needed refinement characteristics.Back to Blog ...