Author Question: What process parameters affect the part quality the most? Discuss 2 or 3 of these parameters and ... (Read 84 times)

Bernana · **on:** Aug 19, 2018

What process parameters affect the part quality the most? Discuss 2 or 3 of these parameters and their specific effects on part quality. Which is the most important for cycle time?

What will be an ideal response?

Question 2

You are asked to specify the material for an extremely large part. The boss says he wants a high MI material. Why would this be beneficial, and what effect would the choice have on material properties? (Density, impact resistance, tensile and flexural properties, etc.)

What will be an ideal response?

raili21 · **Reply #1 on:** Aug 19, 2018

Answer to Question 1

Some of these parameters could be temperature of melt, temperature of mold, pressure of injection and holding, injection or fill-rate and time, dwell time, freeze time, ejection time, etc. The cooling time is the most important for cycle time in injection molding.

Answer to Question 2

The higher the MI the more material will be extruded faster in order to create the really large part. The properties of such a material would result in a part that would have a higher impact resistance because of its higher tensile strength. These characteristics would also assume that the material would have greater flexural properties and lower crystallinity.