| Title |
Effect of P/Al Molar Ratio and Curing Conditions of CBAPC Binder on Flexural Strength and Moisture Resistance of Artificial Sand Core |
| Authors |
오현곤(Hyeon Gon Oh); 박동국(Dongkook Park); 김양도(Yangdo Kim); 이만식(Man Sig Lee) |
| DOI |
https://doi.org/10.3365/KJMM.2019.57.12.808 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
artificial sand; casting; CBAPC binder; flexural strength; moisture resistance |
| Abstract |
CBAPC (chemically bonded aluminum phosphate ceramic) binders have various advantages, including superior corrosion resistance and strength at high temperature. They are also a non-toxic and eco-friendly material. We investigated an inorganic binder based on CBAPC using artificial sand for casting. The CBAPC binders were synthesized with various P/Al molar ratios from 2.0 to 6.0. Specimens were prepared by mixing the artificial sand and CBAPC binder, and then heat-treating at 260 ℃ for 10 min. The prepared CBAPC binders were characterized using TGA/DSC, XRD, FT-IR, and FE-SEM. The artificial sands (Esperal 40, Cps 1) were characterized by XRF, grain size analysis, and FE-SEM. The ultimate flexural strengths obtained for the artificial sands (Esperal 40, Cps 1) were 6.40 and 6.36 MPa, respectively, under the conditions P/Al=4.5, curing temperature=260 ℃, and curing time=10min. The CBAPC_4.5 had higher thermal stability at low temperature than the samples with other P/Al molar ratios. The AlH2P3O10 · 2H2O structure formed at 260 ℃ exhibited high mechanical strength and moisture resistance with improved flexural strength. The effect on the surfaces of the CBAPC_4.5 coated artificial sands depended on the curing temperature and curing time. We confirmed that the P/Al molar ratio and curing conditions strongly affected flexural strength.(Received August 28, 2019; Accepted November 18, 2019) |