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当前英国使用的冷硬粘结剂材料大体分为三类:1、硅酸盐类,2、有机树脂类,3、无机树脂类。它们之中有的是直接与型砂,硬化剂混辗后自行硬化,有的是成型后经通气硬化。水玻璃砂:是使用最古老的冷硬工艺,近百年来中国一直使用这种材料。但英国最近26年开始引进,现已广泛使用。水玻璃的SiO_2/NaO比值在2～3:1之间。用海砂和风积砂。CO_2用量/粘结剂约为1:1。硬化时间低于20秒。型芯保存时间可达数星期。为改善出砂性,改进了一些硅酸盐粘结剂的配方,以丸状形式加入砂中获得较好效果。水玻璃自硬砂:作为硬化剂使用较普遍的有硅酸二钙、硅铁粉和有机酯。前二者的优点
The current British use of chilled binder materials can be divided into three categories: 1, silicate, 2, organic resins, 3, inorganic resins. Some of them are directly with the sand, hardener self-hardening after mixing, and some are formed by the ventilation hardening. Water glass sand: is the use of the oldest chilled process, China has been using this material for nearly a hundred years. However, the UK has started to introduce it in the recent 26 years and is now widely used. The water glass has a SiO 2 / NaO ratio between 2 and 3: 1. Sea sand and wind sand. CO 2 dosage / binder is about 1: 1. Hardening time is less than 20 seconds. Core save time up to several weeks. In order to improve sand production, some silicate binder formulations have been modified to provide better results in the form of pellets added to the sand. Water glass self-hardening sand: as a hardener are more commonly used are calcium silicate, ferrosilicon powder and organic esters. The advantages of the former two