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为了确定更有效的型砂以便降低成本,提高造型效率和使落砂时保持良好环境,研究了由少量快硬水泥和添加剂配制的型砂。外加由无机氧化物生成的促凝剂和主要由β萘磺酸甲■缩合生成的表面稳定剂,在快硬水泥水合初期加大了水合的成度,使之成为硬化粘结致密结构。这种型砂在初期和后期阶段提高了相当高的机械强度,虽然水泥量少,都具有良好的表面稳定性以满足金属浇注。根据温度、石英砂的紧实度和铸型需要的性能(例如机械强度)对100份石英砂而言,由快硬水泥、水、促凝剂和表面稳定剂配制的型砂,推荐的比例确定各自为2—4、3.0-6.0,0.3-3.0和0.4-0.6份。促凝剂和表面稳定剂不充分的铸型,通过造型后在其表面喷涂表面稳定剂或树脂乳状液后,使表面结壳,由于表面稳定性和表面硬度显著改善,从而有效的使铸造工艺没有什么同题。由于水泥含量减少,使游离水分也减少。铸造砂的溃散性和耐火度比以前那些使用大量快硬水泥的配制砂更好。高温负荷度形变如同以前的型砂一样是非常小的。
In order to determine more effective sand in order to reduce costs, improve modeling efficiency and maintain a good environment during sandfall, sands formulated with a small amount of fast cement and additives were studied. In addition, the coagulant formed from inorganic oxides and the surface stabilizer mainly formed by the condensation of beta-naphthalenesulfonic acid, increase the degree of hydration during the early stage of hydration of fast-hardening cement, making it a hard-bonded dense structure. This type of sand has increased mechanical strength in the early and late stages, and although the amount of cement is small, it has a good surface stability to meet the metal casting. According to the temperature, the compactness of the quartz sand, and the required properties of the mold (for example, mechanical strength), for 100 parts of quartz sand, the recommended proportion of the sand prepared from the quick-hard cement, water, coagulant, and surface stabilizer is determined. Each is 2-4, 3.0-6.0, 0.3-3.0, and 0.4-0.6. Insufficient casting accelerators and surface stabilizers are used to cast a surface stabilizer or a resin emulsion on the surface after molding to crust the surface. The surface stability and surface hardness are significantly improved and the casting process is effectively achieved. There is no such thing. As the cement content is reduced, the free moisture is also reduced. Foundry sands have better collapsibility and refractoriness than those previously used with a large amount of fast-hardening cement. The high temperature load deformation is as small as the previous sand.