Injection Molding
9 views
Weld lines of PBT injection molded products are not obvious but the strength is extremely low
Problem Phenomenon
The weld lines of the product are not easy to detect from the appearance, but the actual strength is extremely low.
Cause Analysis
PBT crystallizes quickly, and the weld lines have begun to crystallize in the early stage of mold filling; the glass fiber orientation at the weld lines is unfavorable; the surface fusion looks complete but the interior is not truly bonded.
Solution
Raise the melt temperature and mold temperature to extend the fusion time; increase the injection speed; optimize the gate position.
Key Takeaway
Weak PBT weld lines are a hidden risk and need mechanical testing for verification.
Was this helpful?
0 people found this helpful
Thank you for your feedback!