Liquid shrinkage takes place when the molten metal cools, solidification shrinkage
occurs from the time the first solid metal appears until the casting is completely solid, and solid shrinkage is often called "patternmaker's shrink" because a patternmaker can make a slightly larger pattern than the finished casting dimensions to compensate for the solid shrinkage.
Numerical and experimental investigation of solidification shrinkage
. Numerical Heat Transfer, Part A: Applications, 52(2), 145-162.
In FDM 3-D printing, solidification shrinkage
is the main factor contributing to the detachment of printed shapes from print surfaces because it happens quite rapidly.
Numerical model to predict the position, amount and size of microporosity formation in Al-Cu alloys by dissolved gas and solidification shrinkage
, Materials Science and Engineering A, vol.
While form closure is ensured by the geometric design of the workpiece to be cast, force closure is based on the solidification shrinkage
of the casting material to generate a press fit.
The result is parts with less gas porosity and solidification shrinkage
, higher density, and better strength than conventional die castings.
Indeed, none of the metallographic sections from the many different heats of the alloy cast in this study showed any microporosity attributable to solidification shrinkage
, to a resolution less than 1 [micro]m.
The analysis of the solidification shrinkage
did demonstrate that there is the possibility to get a small deflection in form on the exterior of the product and this was observed in all parts.
If the part is molded to the proportions shown in the screen capture, the relatively thick sections would result in longer cycle times and possible quality problems due to solidification shrinkage
Another shrinkage model based on only the solution of the metal and mold energy equations (not fluid flow equations) can predict porosity by evaluating the volume of the solidification shrinkage
in each isolated liquid region at each time step.
The defects were reduced or eliminated when the fraction solid was reduced to 65-75%, due to the presence of liquid metal that fed the solidification shrinkage
* Integration of the metal delivery geometry with 17-4 PH solidification gradients to provide properly placed sources of liquid to feed solidification shrinkage
at the required Grade B and C integrity levels.