Casting Applications Investment casting is used in the aerospace and power generation industries to produce turbine blades with complex shapes or cooling systems. Blades produced by investment casting can include single-crystal (SX), directionally solidified (DS), or conventional equiaxed blades. It is also widely used by firearms manufacturers to fabricate firearm receivers, triggers, hammers, and other precision parts at low cost. Other industries that use standard investment-cast parts include military, medical, commercial and automotive. Investment casting offers high production rates, particularly for small or highly complex components, and extremely good surface finish (CT4-CT6 class accuracy and Ra1.6-6.3 surface roughness) with very little machining. The drawbacks include the specialized equipment, costly refractories and binders, many operations to make a mold, and occasional minute defects.