湖北汽车工业学院毕业论文.docVIP

湖北汽车工业学院毕业论文 题 目 熔模铸造型壳焙烧助剂及焙烧工艺研究 学生姓名： 田 野 系 别： 材 料 工 程 系 专 业： 材料成型及控制工程 学 号： 20080330118 班 级： T833－1 指导教师： 曾 大 新 摘 要 本课题是开发在较低温度下加快粘接剂、耐火材料等物质之间发生热物理化学变化的烧结助剂，研究焙烧工艺。在面层采用硅溶胶、背层采用水玻璃为粘结剂的复合制壳工艺基础上，在以硅溶胶为粘结剂的涂层中采用硼酸硬化，在水玻璃型壳涂料中加入焙烧助剂及采用硼酸与AlCl3复合硬化液硬化，焙烧助剂有高岭土，NaNO3，Al(OH)3，六偏磷酸钠，硼酸。研究焙烧助剂组成与加入量对700℃焙烧后型壳强度与透气性的影响，找出最佳配方。实验结果表明：硅溶胶型壳撒砂中混入3%的硼酸，水玻璃型壳涂料中加入2-3%的高岭土和3%的NaNO3，水玻璃型壳采用AlCl3：硼酸：水=1:1:4的硬化剂硬化15min可以使型壳性能在700℃焙烧后达到理想效果。 关键词：熔模铸造型壳，低温焙烧，透气性，高温抗弯强度，焙烧助剂 ABSTRACT This theme is to develop sintering aids that can speed up the chemical reaction of the thermophysical under low temperature among substances such as binders, fire-proof materials and so on, and to research roasting technology. Based on the compound shell technology in which silica sol is used as the surface binder of the shell and sodium silicate as the other binders, we use boric acid as the hardening in the surface. In others, we add sintering aids as well as using boric acid and AlCl3 compound hardening solution hardening.These sintering additives including kaolin, NaNO3, Al (OH) 3, sodium hexametaphosphate, boric acid.The above experiments aim at finding out the best formula through analyzing different sintering aids’ influnces on strength and permeability when the shell is roasted at 700℃. The experimental results show that : silica sol shell sanding mixed with 3% boric acid,adding 2-3% kaolin and 3% NaNO3 into sodium silicate shells coatin,Sodium silicate shell hardened 15min by AlCl3: boric acid: water = 1:1:4 hardener to achieve the ideal shell performance after calcination at 700℃. Key words：improvement of shell，low-temperature roasting,high-temperature bending strength,permeability,sintering aids 目 录 第一章 绪 言 - 1 - 1.1 研究目的与意义 - 1 - 1.2熔模铸造焙烧助剂及焙烧工艺研究现状 - 1 - 1.2.1 熔模铸造型壳焙烧的物理化学过程 - 1 - 1.2.2 制壳材料和焙烧温度对型壳焙烧物理化学变化及型壳性能影响 2 - 制壳材料和焙烧温度对型壳强度的影响 2 - 制壳材料和焙烧温度对型壳透气性的影响 4 - 1.2.3低温焙烧型壳材料与工艺研究 4 - 第二章 研究方案与方法