Master Alloy

Al–Sr alloy (Aluminum–Strontium Master Alloy) is an alloy made by adding strontium (Sr) to aluminum (Al). It is primarily used as a modifier for microstructural refinement in Al–Si casting alloys. In Al–Si alloys, silicon crystals tend to form coarse, needle-like structures that reduce mechanical properties. The addition of Sr transforms these into a fine and spheroidized structure, thereby improving toughness and ductility.

Key Features

Silicon Particle Spheroidization: Sr modifies the silicon growth pattern in Al–Si alloys

Improved Mechanical Properties: Enhances tensile strength, ductility, and fatigue life

Reduced Gas Porosity: Minimizes porosity defects during solidification when overmodification is avoided