Dec 7, 2018
All information, which is needed for production, is collected on the machine setup sheet ( or machine datasheet).
It starts with the material and its drying conditions, then it continues with the machine data and the strokes of the mold.
After that, the process parameters follow.
This includes the temperatures of each cooling channel, hot runner and cylinder; cycle times, pressures and speeds.
With a correct filled datasheet, it is possible to reproduce the process anytime.
Jan 8, 2019
Metal Injection Molding is A PIM-process in which fine-powdered metal is mixed with a thermoplastic plastic binder material to a Compound is called metal injection molding. The fine-powdered metals are the feedstock. This feedstock can be processed with plastic injection molding. The plastic injection molding process allows competitive manufacturing of mid to high volumes and mid to high complex part designs.
In a second process step, the molded part is debindered – the thermoplastic binder is removed from the feedstock.
In a third process step, the debindered part is sintered.
Densities of 99,95 % and higher against compact virgin material can be obtained.
Material- and mechanical properties of final processed parts are mostly comparable to the corresponding compact, solid materials.
MIM is very cost competitive against standard multi stage cutting technologies like milling, drilling, grinding, etc.
Best practice examples for MIM-processes: Stainless steel watch-housings, aerospace, textile industry, medical applications and many others.
May 29, 2019
The sequential process during the injection of the melt into the cavity until the part is cooled down, is called mold filling phase.
After the volumetric filling of the cavity (95% to 98% of the cavities volume), (A) there is a switch-over from injection to packing.
During this phase the material is packed and pressed to the mold wall (B).
After the switch over point the complete filling (100%) of the cavity takes place.
During the packing phase (C) the material will be compressed is in good contact with the mold wall.
The plastic shrinks while it is cooling down (approximately 0,2 – 2,0 %).
Shrinkage is compensated in the packing phase due to a material delivery through the melting core. This is important to ensure the dimensions of the part itself.
After the packing phase, cooling phase will start (D). Here the part will be cooled down to a point, where the dimensional stability can be ensured (to ejection temperature) and ejection can be done without deformations on the part.
Jan 28, 2019
If an integration of electronic, optical and mechanical functions is realized in one part, the part is called MID part.
MID is short for the term Molded Interconnected Device. In a newer description, MID is also referred to Mechatronic Integrated Device.
When it comes to injection molding, a part is produced using a thermoplast with additives. With this, the optical and mechanical properties are defined.
After the production, there is a second step (e.g. using the LDS process) in order to activate the additives. This is important to allow metallisation of the part in a third step.
The metallisation is used to create the circuit lines in order to prepare the base for mounting SMD elements for completing the electrical function of an MID part.
Besides this, the MID technology is widely used in creating antenna for mobile communication.
MID-sample model with LED display and sensor pads.
Related topics:
Miniaturization
This glossary of plastic industry is provided by PLEXPERT Canada Inc.
Jul 17, 2019
In injection molding, part inserts are commonly used to produce parts.
First, the part inserts are added into the cavity, after that the melt over molds it on one side.
This is why the process is called “Overmolding”.
The advantage of this process is that the materials are connected due to the hot melt by a strong bond.
Gluing of the different parts is unnecessary in this case.
This process is often used with films as part inserts.
It is important to control the process temperatures since a melting of the insert is not or only partially wanted.
