Research on the Influence of Plastic Viscosity and Product Thickness on Core Penetration Effect of Sandwich Injection Molding

doi:10.19491/j.issn.1001-9278.2021.10.014

Abstract

Abstract:

A sandwich injection?simulation analysis was carried out for a barrel?shaped plastic part using the Moldflow software. The effects of the material viscosity ratio of core to shell and the product wall thickness on the core penetration length， core thickness， and core distribution uniformity of the sandwich injection?molded products were investigated. The results indicated that under the same molding process parameters， the core penetration length ratio decreased in a rate of 1.41 %~1.67 % with an increase in a viscosity ratio of core to shell. Meanwhile， the average value of the core melt thickness ratio increased at a rate of 1.76 %~2.28 %， and the core melt thickness ratio deviation increased at a rate of 1.91 %~2.66 %. As the product wall thickness increased by 1 mm， the core melt penetration length ratio decreased by 1 %~2 %， the average value of the core melt thickness ratio increased by about 6 %， and the core melt thickness ratio deviation increased by about 10 %.

Key words: sandwich injection molding, viscosity ratio, wall thickness, core penetration length, core distribution uniformity

CLC Number:

TQ320.66⁺2

LI Shao, WANG Xiaoxin, ZHOU Lehui, FU Nuofeng, ZHONG Jianquan. Research on the Influence of Plastic Viscosity and Product Thickness on Core Penetration Effect of Sandwich Injection Molding[J]. China Plastics, 2021, 35(10): 83-87.

Figures/Tables 12

References 6

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组号	壁厚/mm	A料	B料	黏度比
1	2.5	PP	PE?LD₁	0.56
2	2.5	PP	PE?LD₂	1.11
3	2.5	PP	PE?LD₃	1.86
4	2.5	PP	PE?LD₄	3.65
5	3.5	PP	PE?LD₁	0.56
6	3.5	PP	PE?LD₂	1.11
7	3.5	PP	PE?LD₃	1.86
8	3.5	PP	PE?LD₄	3.65
9	4.5	PP	PE?LD₁	0.56
10	4.5	PP	PE?LD₂	1.11
11	4.5	PP	PE?LD₃	1.86
12	4.5	PP	PE?LD₄	3.65

组号	壁厚/mm	A料	B料	黏度比
1	2.5	PP	PE?LD₁	0.56
2	2.5	PP	PE?LD₂	1.11
3	2.5	PP	PE?LD₃	1.86
4	2.5	PP	PE?LD₄	3.65
5	3.5	PP	PE?LD₁	0.56
6	3.5	PP	PE?LD₂	1.11
7	3.5	PP	PE?LD₃	1.86
8	3.5	PP	PE?LD₄	3.65
9	4.5	PP	PE?LD₁	0.56
10	4.5	PP	PE?LD₂	1.11
11	4.5	PP	PE?LD₃	1.86
12	4.5	PP	PE?LD₄	3.65

组号	壁厚/mm	黏度比	芯层穿透长度比	芯层厚度因子均值	芯层厚度分布偏差
1	2.5	0.56	0.948 4	0.569 3	0.240 6
2	2.5	1.11	0.947 0	0.606 0	0.244 8
3	2.5	1.86	0.916 5	0.615 7	0.298 0
4	2.5	3.65	0.907 7	0.632 7	0.318 2
5	3.5	0.56	0.932 9	0.603 7	0.277 2
6	3.5	1.11	0.928 8	0.633 0	0.311 3
7	3.5	1.86	0.904 9	0.652 0	0.320 7
8	3.5	3.65	0.883 4	0.665 0	0.353 6
9	4.5	0.56	0.912 7	0.645 4	0.316 8
10	4.5	1.11	0.923 4	0.641 8	0.356 1
11	4.5	1.86	0.887 6	0.699 9	0.362 3
12	4.5	3.65	0.870 1	0.709 1	0.385 6

组号	壁厚/mm	黏度比	芯层穿透长度比	芯层厚度因子均值	芯层厚度分布偏差
1	2.5	0.56	0.948 4	0.569 3	0.240 6
2	2.5	1.11	0.947 0	0.606 0	0.244 8
3	2.5	1.86	0.916 5	0.615 7	0.298 0
4	2.5	3.65	0.907 7	0.632 7	0.318 2
5	3.5	0.56	0.932 9	0.603 7	0.277 2
6	3.5	1.11	0.928 8	0.633 0	0.311 3
7	3.5	1.86	0.904 9	0.652 0	0.320 7
8	3.5	3.65	0.883 4	0.665 0	0.353 6
9	4.5	0.56	0.912 7	0.645 4	0.316 8
10	4.5	1.11	0.923 4	0.641 8	0.356 1
11	4.5	1.86	0.887 6	0.699 9	0.362 3
12	4.5	3.65	0.870 1	0.709 1	0.385 6

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