For broader context, compare this topic with conception de moules d'injection<\/a>et supplier sourcing guide<\/a>.<\/p>\n Flow marks are visible surface imperfections on injection molded parts that appear as wavy lines, ripple patterns, or bands of slightly different color or gloss. They form when the advancing melt front cools unevenly against the mold wall, creating a wrinkled or folded skin that gets frozen into the final part surface. In our factory, flow marks rank among the top three cosmetic defects that cause part rejections\u2014particularly for consumer-facing products where surface appearance is critical.<\/p>\n Bien que les marques d'\u00e9coulement affectent rarement l'int\u00e9grit\u00e9 structurelle de la pi\u00e8ce, elles donnent aux produits un aspect inachev\u00e9 et non professionnel. Pour les panneaux int\u00e9rieurs automobiles, les bo\u00eetiers d'\u00e9lectronique grand public et les enceintes de dispositifs m\u00e9dicaux, m\u00eame des marques d'\u00e9coulement mineures peuvent d\u00e9clencher des rejets qualit\u00e9 qui retardent les calendriers de production et augmentent les co\u00fbts. Comprendre la cause racine \u2014 l'interaction entre la vitesse du front de fusion, la temp\u00e9rature et la surface du moule \u2014 est la premi\u00e8re \u00e9tape vers l'\u00e9limination de ce d\u00e9faut. La bonne nouvelle : dans la plupart des cas, les marques d'\u00e9coulement peuvent \u00eatre enti\u00e8rement r\u00e9solues par des ajustements des param\u00e8tres de processus sans aucune modification du moule.<\/p>\n Melt temperature is the single most influential process parameter for flow marks. When the melt temperature is too low, the plastic skin solidifies prematurely against the mold wall, creating drag and wrinkle patterns as the still-flowing core pushes the solidified skin forward. We\u2019ve found that a 10\u201320\u00b0C increase in melt temperature eliminates flow marks in roughly 50% of cases without any other changes.<\/p>\n We always increase temperature in 5\u00b0C increments and evaluate 10 shots at each level. Going too high risks material degradation, yellowing, or increased marques d'\u00e9vier<\/a> due to lower melt viscosity during packing.<\/p>\n\n
![\"D\u00e9fauts](\"https:\/\/zetarmold.com\/wp-content\/uploads\/2026\/02\/800x457_insert_6.jpg\")
How Does Melt Temperature Affect Flow Mark Formation?<\/h2>\n
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\n \nMat\u00e9riau<\/th>\n Standard Melt Temp (\u00b0C)<\/th>\n Recommended Temp to Reduce Flow Marks (\u00b0C)<\/th>\n Maximum Safe Temp (\u00b0C)<\/th>\n<\/tr>\n<\/thead>\n \n ABS<\/td>\n 220\u2013240<\/td>\n 240\u2013260<\/td>\n 270<\/td>\n<\/tr>\n \n PC<\/td>\n 280\u2013300<\/td>\n 300\u2013320<\/td>\n 330<\/td>\n<\/tr>\n \n PP<\/td>\n 200\u2013230<\/td>\n 230\u2013250<\/td>\n 270<\/td>\n<\/tr>\n \n PMMA<\/td>\n 220\u2013240<\/td>\n 240\u2013260<\/td>\n 270<\/td>\n<\/tr>\n \n PA6<\/td>\n 240\u2013260<\/td>\n 260\u2013280<\/td>\n 290<\/td>\n<\/tr>\n \n POM<\/td>\n 190\u2013210<\/td>\n 200\u2013215<\/td>\n 220<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n