【作者】 王春雷；

【导师】 邹海峰；

【作者基本信息】 吉林大学 ， 化学工程（专业学位）， 2020， 硕士

【摘要】 以研发一种新型、高效、节能、环保的冷芯盒制芯材料及其在缸体铸件砂芯上应用为目标,使其满足既具有优异的工艺性,又能适合绿色、环保的铸造生产大批量制芯的需求。论文研究取得以下成果:（1）优化了酚醛树脂本体合成工艺确定最佳的工艺参数和原材料配比,得到了具有较高强度的甲阶酚醛树脂本体。采用分段升温等工艺方式,以Na OH为催化剂,由甲醛和苯酚等材料在碱性催化剂作用下通过缩合反应获得/制备。技术参数为:Na OH浓度（质量分数）为0.06～0.08%,苯酚与甲醛的摩尔比为1:2.0～2.5,保温反应时间控在150 min,通过粘度测量灵活控制反应终点,粘度控制在25～30 mpa.s。（2）优化了CO₂气硬酚醛树脂粘结剂制备的工艺条件通过正交试验确定了最佳实验条件,酚醛树脂:氢氧化钾:硼砂:硅烷=100:45:16:1。利用加入多种活性基团（催化剂、含有醚键的环状醚醇等）改善了粘结剂的性能,增强了砂型（芯）的强度和稳定性,改善了树脂砂的流动性等。（3）研究了CO₂硬化酚醛树脂粘结剂性能改进的机理确定了CO₂硬化酚醛树脂粘结剂型（芯）砂的树脂加入量、使用时间、溃散性、发气量等工艺参数,通过核磁共振波谱分析仪、红外光谱分析仪、扫描电镜等检测手段研究了粘结剂吹气硬化的机理。（4）完成了粘结剂制备中试试验和生产应用验证了酚醛树脂粘结剂的制备工艺,为粘结剂的批量生产优化了最佳工艺参数。在某公司中试基地现场进行了多次制芯生产验证,成功地浇注了多件灰铁缸体铸件。制芯现场无毒无味,制备的砂芯强度较高,溃散性良好,清理方便,无铸造缺陷。研发的气硬冷芯盒粘结剂能够满足现场铸造生产的要求,生产应用取得了良好的经济效益、社会效益和环保效益。更多还原

【Abstract】 A new type of cold box core material with high efficiency,energy saving and environmental protection and its application in sand cores of cylinder block castings are studied.It has excellent technological properties and is suitable for mass production of green and environmental protection foundry.The following results have been achieved in this paper:（1）The bulk synthesis process of phenolic resin was optimized.The phenolic resin body with high strength was obtained by determining the optimum technological parameters and raw material ratio.The condensation reaction of formaldehyde and phenol was carried out with Na OH as catalyst under the action of alkaline catalyst.The technical parameters are as follows:Na OH concentration（mass fraction）is 0.06-0.08%,the molar ratio of phenol to formaldehyde is 1:2.0-2.5,the reaction time is controlled at 150 minutes,the end point is flexibly controlled by viscosity measurement,and the viscosity is controlled at 25-30mpa.s.（2）The technological conditions for the preparation of CO₂ pneumatic phenolic resin binder were optimized.The optimum experimental conditions were determined by orthogonal test,phenolic resin:KOH:borax:silane=100:45:16:1.The properties of the binder,the strength and stability of sand moulds（cores）and the fluidity of resin sand were improved by adding various active groups（catalysts,ether bonds containing cyclic ether alcohols,etc.）.（3）The mechanism of improving the properties of CO₂-hardened phenolic resin binder was studied.The technological parameters of resin addition,service time,collapsibility and gas emission of CO₂ hardened phenolic resin bonding sand were determined.The mechanism of blowing hardening of the bonding agent was studied by means of NMR,IR and SEM.（4）The pilot test and production application of binder preparation have been completed.The preparation process of phenolic resin binder was verified,and the optimum process parameters were optimized for the mass production of the binder.In a pilot plant of a company,several core-making production tests were carried out on site,and many gray iron cylinder castings were successfully poured.The core-making site is non-toxic and odorless.The prepared sand core has high strength,good collapsibility,easy cleaning and no casting defects.The air-hardened cold-box binder developed can meet the requirements of field casting production.Good economic,social and environmental benefits have been achieved in production and application.更多还原