A master alloy is aluminium carrying a high, controlled percentage of another element. It lets foundries and cast houses add that element accurately at normal melt temperatures, where the pure element would dissolve slowly or oxidise. The names give the content: AlTi5B1 has about 5% titanium and 1% boron; AlSr10 has about 10% strontium; AlSi50, AlMn20 and AlCu50 carry silicon, manganese and copper.
Main groups
- Grain refiners such as AlTi5B1 and AlTi3B1; see grain refiner.
- Modifiers such as AlSr10, which refine eutectic silicon in alloys like LM6 and A356.
- Hardeners for alloying with Si, Mn, Cu, Fe, Cr and others.
Why it matters when buying
- Check nominal content and tolerance on the certificate, and the distribution of particles for refiners.
- Form matters: waffle ingot, rod in coils for continuous feeding, or tablets.
- Fluxes for cleaning and degassing are often bought alongside; ask for handling and storage advice, since many are moisture sensitive.
- Small dosing errors show up in the final chemical composition, so traceability by lot is important.
Browse master alloys and fluxes.