Investment Casting

Sponsors: 

 

 

 

 

 

Investment Casting

OVERVIEW

When determining the type of investment casting to use, you must first determine the final purpose of the product. Some of the types include: stainless steel casting, aluminum alloy casting, carbon steel casting, brass and bronze casting, lost wax casting, cobalt casting, tool steel casting, metal casting and rapid prototype casting.
 
The investment casting process begins by producing a heat disposable pattern. This is accomplished by injecting wax or plastic into a metal die. A pattern must be molded for every casting. The patterns are assembled into a cluster (or tree) and are then coated with various liquid ceramic refractories to form a ceramic shell. The wax or plastic is then melted out of the ceramic shell.
 
Any number of different alloys can be cast into the ceramic mold. After cooling, the ceramic shell is removed and the castings are cleaned.

ADVANTAGES

  • Excellent surface finish
  • High dimensional accuracy
  • Extremely intricate parts are castable
  • Almost any metal can be cast
  • No flash or parting lines

TOLERANCES

  • A casting process typically maintains dimensional accuracy of +/-.005" per inch, with a surface finish of 125 RMS or better.

FINISHES

  • There are many finishing options once the casting is complete. Treatments that can be applied to investment castings include everything from rust protection (with carbon and low alloy steels) to complex corrosion enhancing polishing and painting treatments.

MATERIALS AVAILABLE

  • MFG.com suppliers produce investment castings in most air melt alloys including 300 & 400 stainless steels, nickel base, cobalt base alloys, as well as carbon and high alloy steel grades.