The Research On Air-Hardened Aqueous Alkaline Phenolic Resin Sand

The 21st century is the swift and violent development and the times of product quality, production cost and environmental protection keen competition of new and high technology of our country. Therefore developing high quality, pollution-free, low molding sand binder of cost become demand of era. As a new type, high-efficient and energy-conservation making core material, air-hardened resin bonder caused the extensive attention of the domestic and international scholar since generation.In summary, this study is divided into several sequences as follows:Firstly, the synthesis of alkaline phenol-aldehyde resin was been reached. According to adding pyrocatechol, hydrochinone, and bisphenol A, which modify synthesis of phenolic resin and analyse effect of all the factors on the properties of the resin sand. The optimum synthetic process has been achieved and the optimum technological parameters of the synthetic resin and the prescription of the raw materials have been got. Consequently, an alkaline phenol-aldehyde resin desired binding function has been obtained.Secondly, phenolic resin cross-linking agent and coupling agent and organic active agent have been researched systematically. Through single-factor experiment, effect of alkali, natrium biboricum and silane addition on phenolic resin compressive strength have been studied, the optimum addition range has been defined and the optimum prescription of amount has been found out by orthogonal designs. What is more, the effect of A agent, B agent and D agent etc coupling agent and organic active agent on phenolic resin compressive strength have been reached, hardening mechanism of the resin binder also has been discussed.In the next, bench time, gas evolution, collapsibility and amount of CO2 -hardening alkaline resol phenol-aldehyde resin binder composition have been tested. It has preferable technological properties.Finally, production test and economic-analysis have been made. The sand moulding with the air-hardened resin bonder is used to make a Al-alloy casting. Through production test, the new binder can meet the requirement of the foundry industry and"green cast". The economic-analysis show that the air-hardened resin bonder will has excellent practical production value and economic benefits when it compared with currency binder with (C2H5)3N.