CastingCasting

Mukul GuptaMukul Gupta

ID#20195018ID#20195018

4M-L4M-L

CastingCasting A manufacturing process used to solidify objects A manufacturing process used to solidify objects

from their liquid form into various useful shapes from their liquid form into various useful shapes by introducing a fluid melt into a mold.by introducing a fluid melt into a mold.

Four main elements Four main elements PatternPattern MoldMold CoresCores the partthe part

Subdivisions of CastingSubdivisions of CastingExpendable mold casting:Expendable mold casting:

Sand CastingSand Casting Plaster casting (of metals)Plaster casting (of metals) Plaster casting (of plaster or concrete)Plaster casting (of plaster or concrete) Shell moldingShell molding Investment CastingInvestment Casting

Nonexpendable mold casting:Nonexpendable mold casting:Permanent Mold CastingPermanent Mold Casting Die CastingDie Casting Centrifugal casting Centrifugal casting Continuous casting Continuous casting

Cooling rateCooling rate The rate at which a casting cools affects it The rate at which a casting cools affects it

microstructure, quality, and propertiesmicrostructure, quality, and properties

Slower Cooling: Slower Cooling: Increases the metal's grain sizeIncreases the metal's grain size Resluting in a coarse microstructureResluting in a coarse microstructure allows more gases and waste metal to escape, allows more gases and waste metal to escape,

reducing the voids and inclusions that can reducing the voids and inclusions that can weaken a castingweaken a casting

Faster Cooling:Faster Cooling: resulting in a fine microstructure with small grain resulting in a fine microstructure with small grain

and less alloy segregation and less alloy segregation more trapped gases and inclusionsmore trapped gases and inclusions

ShrinkagShrinkagee

The shrinkage caused by solidification can leave The shrinkage caused by solidification can leave cavities in a casting, weakening it.cavities in a casting, weakening it.

Risers provide additional material to the casting Risers provide additional material to the casting as it solidifiesas it solidifies

Add CostsAdd Costs

Why does shrinkage occursWhy does shrinkage occurs Metals are less dense as liquids than as solids, Metals are less dense as liquids than as solids,

castings shrink as they coolcastings shrink as they cool

ReferencesReferences

http://en.wikipedia.org/wiki/http://en.wikipedia.org/wiki/Casting#Casting_in_manufacturingCasting#Casting_in_manufacturing

http://en.wikipedia.org/wiki/Riser_http://en.wikipedia.org/wiki/Riser_%28casting%29%28casting%29