Work

Effect of Hydrophobic Fumed Silica on Bending Strength of Sodium Silicate-Bonded Sand Cores

Year: 2024

Type: article

Abstract: Inorganic sand cores involving sodium silicate binder and microsilica have environmental advantages during the casting process of aluminum alloy. Nevertheless, the bending strength of sodium silicate-bonded sand (SSBS) needs to be further improved. In this research, the effect of hydrophobic fumed silica on the bending strength of sand cores was studied. The experimental results revealed that hydrophobic fumed silica with the addition of 0.050 wt.% can be adopted as an optimal modifier to enhance the bending strength of SSBS. According to scanning electron microscope and spectroscopy techniques, dense bonding bridges and a complex Si-O-Si network containing specific silicon molecules with a silicon atom bonded to three other silicon atoms contribute to the excellent bending strength, with a 53.1% increase in cold strength (24 h) compared to a commercial sample of a modified sand core. Meanwhile, the newly formed Si-O-Al chemical bond plays a crucial role in increasing the bending strength of sand cores.

Source: Materials

DOI: 10.3390/ma17235714

Authors: Yunbo Li, Huarui Zhang, Jiulong Chen, Ting Xiang, Ying Cheng, Hu Zhang

Institution: Beihang University

Language: English

Topic: Materials Engineering and Processing

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $2,955