Study on processing⁃structure⁃properties of selective laser sintered of polypropylene

doi:10.19491/j.issn.1001-9278.2023.10.007

Abstract

Abstract:

In this paper， the processability and mechanical properties of commercial polypropylene were systematically evaluated， and the differences between sinter laser sintering （SLS） and injection molding were compared. The results indicated that preheating temperature， laser power and energy density were three important process parameters for SLS to generate a great impact on the performance of final products. When the process parameters were selected， both mechanical properties and machining accuracy should be considered. This study exhibits uniqueness in the quantitative analysis of the crystal forms of the selective sintering strips under different technological conditions， and the relationship between technological conditions， crystalline properties， and mechanical properties was established. Through adjusting the process parameters of SLS， different crystal contents could be obtained for molded samples， and therefore then the mechanical properties of the sample could be regulated.

Key words: polypropylene, selective laser sintering, process parameter, crystal form, mechanical property

CLC Number:

TQ325.1⁺4

ZHANG Hengyuan, LIU Tao, ZHANG Shijun, LIU Jianye. Study on processing⁃structure⁃properties of selective laser sintered of polypropylene[J]. China Plastics, 2023, 37(10): 50-55.

Figures/Tables 21

References 14

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预热温度/ ℃	激光功率/ W	扫描间距/ mm	扫描速度/ mm·s^-1	能量密度/ J·mm^-3
134	35	0.3	7 600	0.15
135	35	0.3	7 600	0.15
136	35	0.3	7 600	0.15
137	35	0.3	7 600	0.15

预热温度/ ℃	激光功率/ W	扫描间距/ mm	扫描速度/ mm·s^-1	能量密度/ J·mm^-3
134	35	0.3	7 600	0.15
135	35	0.3	7 600	0.15
136	35	0.3	7 600	0.15
137	35	0.3	7 600	0.15

熔融焓/J·g^-1	结晶度/%	γ/（γ+α）/%	γ晶型含量/%
54.02	25.81	47.43	12.24
42.66	20.38	45.28	9.23
67.96	32.47	36.93	11.99
71.04	33.94	36.45	12.37

熔融焓/J·g^-1	结晶度/%	γ/（γ+α）/%	γ晶型含量/%
54.02	25.81	47.43	12.24
42.66	20.38	45.28	9.23
67.96	32.47	36.93	11.99
71.04	33.94	36.45	12.37

拉伸强度/ MPa	标称应变/%	弯曲强度/ MPa	冲击强度/ kJ·m^-2	热变形温度/℃
25.45±0.33	10.73±2.23	27.53±1.40	3.55±0.67	82.75±3.61
26.60±0.64	11.15±1.70	28.59±2.55	3.41±0.74	83.25±1.91
25.96±0.36	13.25±2.02	28.02±2.46	3.88±0.56	84.75±3.43
28.18±0.32	20.96±3.43	29.91±0.90	3.24±0.69	88.20±1.98