Preparation of lightweight sheet molding compound using glass balloon filler: improvement of strength, and a novel balloon treatment for better adhesion with the matrix

This paper presents the synergistic effect on flexural properties of kenaf-glass (KG) mat reinforced unsaturated polyester (UPE) hybrid composite which can compounded using sheet molding compound (SMC) process. The matrix is kept constant with 70 % volume fraction while kenaf and glass fibers were varied, such as 7.5/22.5 v/v, 15/15 v/v and 22.5/7.5 v/v. The 30 % kenaf and 30 % glass are also used for the preparation of composite materials. The kenaf mat was treated with 6% sodium hydroxide (NaOH) diluted solution for 3 hours. This mercerization process improved the interface by interacting with both the fiber and its matrix. The flexural test was performed using ASTM D790-03 standard. The study showed with the addition of kenaf and glass mat 15/15 v/v, the optimum flexural properties was obtained compared to other composition. This can be concluded that 15/15 v/v KG mat reinforced unsaturated polyester hybrid composite is the most appropriate hybrid composite which can be considered for many engineering structural applications mainly in automotive panel, bottom structure and bumper beam.

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Coupled effect of loading frequency and amplitude on the fatigue behavior of advanced sheet molding compound (A-SMC)

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684416682853 ◽

2016 ◽

Vol 36 (4) ◽

pp. 271-282 ◽

Cited By ~ 9

Author(s):

M Shirinbayan ◽

J Fitoussi ◽

F Meraghni ◽

B Surowiec ◽

M Laribi ◽

...

Keyword(s):

Fatigue Tests ◽

The Self ◽

Tension Stress ◽

Loading Frequency ◽

Compound A ◽

Molding Compound ◽

Sheet Molding Compound ◽

Self Heating ◽

Coupled Effect ◽

The Matrix

This paper presents the experimental results of tension-tension stress-controlled fatigue tests performed on advanced sheet molding compound (A-SMC). It aims at analyzing the effect of fiber orientation, loading amplitude, and frequency on the fatigue response and the related temperature evolution due to the self-heating phenomenon. Two types of A-SMC have been analyzed: randomly oriented (RO) and highly oriented (HO). The coupled effect of the loading amplitude and the frequency has been studied. It has been shown that the couple frequency-amplitude affects the nature of the fatigue overall response which can be governed by the damage mechanisms accumulation (mechanical fatigue) and/or by the self-heating (induced thermal fatigue). For fatigue loading at 100 Hz, self-heating has been observed and yielded to a temperature rise up to 70℃. The latter causes a decrease of the storage modulus related to the β-transition of the vinylester. It has been demonstrated that the self-heating produced a material softening and decreased the fatigue life. SEM observations revealed that the samples tested at 100 Hz, exhibit smooth debonding surfaces due to the induced thermal softening of the matrix whereas more brittle fracture of the matrix surrounding fibers is observed during the fatigue tests achieved at 10 Hz.

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