Cause of deformation (warpage)
Deformation and dimension change by warpage are often being a problem of PBT resin molded product. Following factors are the cause of the warpage deformation, but actually it will happen when several factors overlap intricately
【 Cause of warpage deformation 】
① Design ・ Lack of shape stiffness
・ Uneven thickness
・ Shape asymmetric property
② Material property ・ Crystalline
・ Anisotropy
・ Lack of material stiffness
③ Molding process ・ Resin and filling material orientation
・ Uneven inner pressure
・ Uneven cooling speed (mold temperature)
・ Shrinkage restriction by mold core
④ Fabricating ・ Thermal process (printing paint, adhesive setting process)
・ Aftercontraction
・ After processing, After insert
⑤ Usage environment ・ High and low temperature atmosphere
・ Creep