Shanghai Daoqin Plastics Co., Ltd.

         plastics internal stress is in plastics melt processing process in due to to large separation orientation and cooling shrinkage and other factors generate types inner in force. large separation 子链间 function force and versus 互缠结 force 蒙受不住 this type of can 时, internal stress balanced to bad, plastics products generate force cracking and warpage deformation and other phenomenon.

         plastics internal stress testing methods

         solvent agent method

        1, acid 沉浸

         use acid (CH3COOH)必 must is 95% above acid 且反复 use 次数不 ultra- 10次 testing.

        ① surface force testing: will acid (冰醋 acid)倒入玻璃 device in, will product full in acid 里, time is 30秒. 30秒 rear use will sample 取出并马 upper use water (自 water can)冲刷清洁, sample surface has 无发白 and cracks. 断定: has cracking phenomenon, surface has micro 发白.

        ② internal stress testing: will surface force testing and sample scratch dry rear full in acid 里, time is 2 separation 钟. 2 separation rear will sample 取出并当即 use water (自 water can)冲洗 dry 净, sample has 无发白 and cracks. 判断: has fracture phenomenon, can parts has light micro cracks and surface phenomenon.

        2, ketone + 丙 ketone method

         will machine 完整浸入21摄氏 degree 1:1 甲乙 ketone + 丙 ketone mixed liquid in, rear 即时甩 dry, upper method 检讨.

         principle: according to 介质应 force phenomenon, solvent separation 子渗透 to resin large separation between rear, reduce separation between function force. internal stress large in front separation between function force 原 就 has low, solvent rear this decrease low 处 进一步 decrease low, 而引起 cracking, internal stress small in short time inner cracking. therefore, can from parts surface cracking time and degree 断定镀 parts internal stress large small and its 部位. from 而断定 plastics parts is 否进行 electroplating.

        仪 device method

         use light plastics made parts, color color light belt/tape more 寡, internal stress strong/high low, it suitable for transparent made parts. light method need device 昂贵, as 庞杂, positive degree high, is made parts front rear 变化不 significantly, light belt/tape upper light belt/tape 不一定都 is internal stress effect/influence, made parts surface 涟漪也会 effect/influence formed 果. outer method for made parts machine can 尚无任何 effect/influence, is loss 检验, 经检验 made parts can electroplating and use.

         temperature degree method

         this type of methods is will plastics parts heavy cold hot, based on cracks time is non internal stress large small. it used for type plastics formed parts. temperature degree method need 装备简略, however time relatively long. 经检修 rear plastics parts already by loss bad, can application.