Strontium Rods and Sticks

Product Development

A large proportion of aluminium casting alloys contain silicon in the range 5-12%. Unmodified melts of these alloys contain coarse, plate-like crystals of eutectic silicon formed during solidification. These particles are brittle and reduce the strength and ductility of the casting. They also tend to decrease the soundness of the casting by inhibiting the flow of molten metal (feeding) in to areas of the casting as it solidifies.

With Strontium modification, a preferred cast structure is developed in which the silicon phase is fibrous and finely dispersed. This preferred structure gives improved mechanical properties, particularly ductility and machinability to the casting.

KB Alloys Sr master alloy offers convenient, stable and effective sources of strontium for the foundry.

KB Alloys has developed a new process for the production of Sr rod and sticks. This process gives a cleaner, more uniform metallurgical structure and keeps KB Alloys at the forefront of technical innovation for the foundry man.

Metallography

Note: Material safety data sheets are available on request. Customers are advised to preheat this product before use to eliminate moisture and thereby prevent possible explosions when material is added to molten aluminium.

The chemistry is as follows:

Structure

DC Cast / Extruded rod Continuous cast / Conform rod
(100x) (100x)

Technical data is taken from a representative production batch of both processes.

Aluminum Strontium is produced in 9.5mm wire which can be layer wound to coils from 180kgs to 1500kgs in weight. Wire can be cropped to sticks of 330mm, 500mm and 1000mm. Cut Cast Bar is trapezoidal bar measuring about 45mm x 25mm. This can be cut to various lengths to suit customer requirements and is available with 3.5%, 5%, 10%, or 15% strontium content.

Click here for information on Aluminum Strontium»

Form	Plates Average	Maximum
Old Process
SrAl4 Typical	106 microns	130 microns
SrAl4 Maximum	276 microns	350 microns
New Process
SrAl4 Typical	24 microns	30 microns
SrAl4 Maximum	96 microns	120 microns

Sr	9.0 – 11.0%
Fe	0.30% max
Si	0.30% max
P	0.01% max
Mg	0.10% max
Ba	0.10% max
Ca	0.10% max
Others each	0.04% max
Others Total	0.10% max
Balance	Aluminium