Foundry Core Mixtures with Orthophosphoric Acid and Different Aluminum-Containing Compounds
The scientific and practical issues of the development of core mixtures for foundry, based on phosphate binding materials, are considered. The binder presented in this article differ from those previously known by the fact that scarce prepared metal phosphate binding components and powder solidifiers are not used to produce them. As a result, all developed binders are different forms of aluminum phosphates. It is shown that to obtain them it is possible to use combinations of orthophosphoric acid with aluminum-containing materials of different chemical nature.
The formation of high-strength phosphate binders in the interaction of phosphoric acid with aluminosilicates and sludge wastes of aluminum production has been established. They are rationally used for processes of thermal strengthening of cores in the temperature range of 200…300 °C.
The formation of binders in the interaction of orthophosphoric acid with inorganic aluminum salts are theoretically proved and practically confirmed. The results are confirmed by thermodynamic calculations, as well as by X-ray phase analysis.
The compositions of the developed core mixtures and examples of their application for obtaining high-quality castings from iron and steel are presented.
. S.P. Doroshenko, V.P. Avdokushyn, K. Rusin, I. Matsechek, Molding materials and mixtures (Vyshcha shkola, Kyiv, 1990).
. A.N. Boldin, N.I. Davydov, S.S. Zhukovsky, T.N. Kiryukhina, N.N. Kuzmin, S.D. Teplyakov and A.I. Yakovlev, Foundry molding materials. Forming, core mixtures and coatings: a Handbook (Mashinostroyeniye, Moscow, 2006).
. V.A. Kopeikin, V.S. Klementieva and B.L. Krasnyy, Refractory phosphate binders, (Metallurgiya, Moscow, 1986).
. Zhang Youshou, Liu Dong, Xia Lu, Ren Yanzhen, Cai Peng, Zhou Lei, Patent China No. 108907069 (30 November 2018).
. Yang Yang, Patent China No. 106734858 (31 May 2017).
. S. Alferyev, V. Polyakov, Patent USA No. 2014175323 (26 June 2014).
. Kim Jai Ha, Hur Yang Wook, Son Sung Han, Joo Kyoung, Patent Korea No. 20090058977 (10 June 2009).
. Xia Lu, Ren Yanzhen, Zhang Qian, Zhang Youshou, Liu Dong, Zhou Lei, Patent China No. 108405794 (17 August 2018).
. Jung Yeon Gil, Kim Eun Hee, Woo Ta Kwan, Lee Je Hyun, Patent Korea No. 20180017400 (21 February 2018).
. Jing Jinlong, Chen Xuegeng, Patent China No. 104815943 (5 August 2015).
. R.V. Lyutyy, D.V. Keush, Ye.A. Anisimova, Patent Ukraine No. 99789 (25 June 2015).