Product Description
Microcellular
Injection Molding analysis simulates the development of cells in
the melt during injection molding.
Note: Not supported for 3D.
The microcellular foam process, often referred to as MuCell process
(developed by Trexel. inc?), works by heating and pressurizing a
non-flammable gas such as nitrogen or carbon dioxide to a
supercritical state, as illustrated in (a) below, which has
characteristics similar to a fluid and produces a foaming agent, as
illustrated in (b) below. Once this process has taken place within
the barrel, the foaming agent is then injected into the plastic
melt as indicated below:
Figure 1. Microcellular molding process. a) SCF is injected
into the barrel/melt through the control valves. b) Gas is
dissolved in polymer melt to form single phase solution.
Through the injection of the tiny uniform cell structure, higher
properties at lower densities is retained more so than is seen with
conventionally foamed parts. This allows molding of thin, light
parts, producing parts that are not brittle. The reduced amount of
resin in the parts also helps reduce cycle times.
In addition, the process reduces clamp force requirements for
molding. This is because the super-critical foaming agent acts as a
solvent, which lowers the viscosity of the material by ****0%, so
lower pressure is required to push the material into the mold
cavity. The process can be run at temperatures as much as **0ᄁXF
below normal.
The Process
The microcellular processing consists of three main steps:
1. Gas dissolution-In the plastication section of
the injection molding process, a supercritical fluid SCF of blowing
agent (CO2 or N2) is injected in to the polymer to form a
single-phase solution. The gas is dissolved in the polymer melt due
to applied high pressure.
2. Nucleation and bubble growth (foaming). There
are two types of processes, either short shot or full
shot:
o Short-shot process-The mixture is injected into
the mold cavity as a short shot to fill only part of the cavity.
Due to the substantial and rapid pressure drop, the solution of the
gas in the melt becomes supersaturated and a large number of
bubbles nucleate and grow to fill the rest of the cavity.
o Full-short process-The mixture is injected to
fill the mold cavity completely. After the cavity is volumetrically
filled, it is pressurized and the nozzle is shut off. The material
within the cavity then shrinks and foams as the pressure
falls.
3. Solidification-During the foaming process the
mold is continuously cooled down, creating the internal cellular
structure. The result is a foamed material with cell size of around
****0 microns, the actual size depending on processing conditions.
The lack of a formal packing phase reduces the residual stress in
the material and results in extremely low warpage.
Capabilities
Microcellular Injection Molding analyses can help to:
" Reduce manufacturing costs.
" Improve material process ability: reducing the
amount of resin in the parts.
" Reduce cycle time.
" Low warpage, and eliminate sink
marks.
" Provide useful information to detect various
molding problems and to optimize part, mold, and process design in
an efficient and cost-effective way.
" Lower the viscosity of the material by
****0%.
" Mold thin, light parts, producing parts that
are not brittle.
Country: |
China |
Model No: |
-
|
FOB Price: |
(Negotiable)
Get Latest Price
|
Place of Origin: |
- |
Price for Minimum Order: |
- |
Minimum Order Quantity: |
- |
Packaging Detail: |
Wooden case package & follow customers' requirement |
Delivery Time: |
15-70workdays |
Supplying Ability: |
- |
Payment Type: |
- |
Product Group : |
printer mold
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