Review Article
Bihari AK, Ramachandran M an
Abstract
We know different casting processes like sand casting, gravity die casting, low pressure die casting, pressure die casting, counter pressure die casting, and centrifugal casting, spin casting, lost wax and lost foam casting. But lost wax or lost foam casting process are going to be most acceptable way of castings to get the intricate and complex shaped castings. Lost wax process is generally known as “Investment casting process”. About 5000 years ago the Egyptians used this process in the time of Pharaohs to make gold jewellery, which was the way of their investment hence the names comes. Ancient “lost wax process” domination for producing beautiful sculptures turns into a present day near net shape manufacturing of intricate engineering components. The journey begins with the development of Investment casting process by Dr. William H. Taggart of Chicago who wrote a detailed study on Investment casting process in 1907. Today’s Investment casting is a versatile process. It is used to manufacture parts ranging from turbocharger wheels to golf stick heads, from electronic boxes to hip replacement implants, General engineering to aerospace, automobiles to pump industries particularly impellers. In this paper we are discussing about the key parameters of the investment casting process which will give a more dimensional accuracy and best surface smoothness and hardness for the mold. The pre-conditions for the mold are discussed and possible defects can occur in the mold and the rectification also analysed experimentally.