IMPACT PROPERTIES OF A356-T6 ALLOYS

The Charpy impact energy of A356 alloys has been measured. Instrumente d Charpy impact tests have been conducted at 25, 100, 150, and 200-deg rees-C. The Charpy specimens were machined from plate castings or tape red cylindrical castings. The plates were produced in sand molds, and tapered cylinders were produced in water-cooled copper molds. Both unm odified and strontium-modified castings were tested. The results indic ate that strontium modification improves the impact properties of sand and permanent mold castings. The impact energy increases with solutio n treatment time. Strontium modification reduces the solution treatmen t time for attaining a specific impact property level in the casting.