改性凹土基碳钢表面涂料的制备与性能研究  

Preparation and properties of modified attapulgite-based carbon steel surface coatings

作　　者：姚义俊[1] 胡义秋 刘斌[1] Yao Yijun;Hu Yiqiu;Liu Bin

机构地区：[1]南京信息工程大学化学与材料学院

出　　处：《耐火材料》2019年第5期394-397,共4页Refractories

基　　金：2019年省级大学生创新训练一般项目(201910300148Y)

摘　　要：以d 50=3.5μm的盱眙凹土粉为原料,经提纯、改性处理后,添加不同量的铝矾土、氧化锆、二氧化硅、碳粉、聚丙烯酸铵、甲基纤维素等,经球磨制成固含量为50%(w)的防氧化涂料,并进行了干燥试验和对碳钢片的氧化试验。结果表明:1)在凹土粉末中添加少量六偏磷酸钠和吐温20型活性剂,经球磨、超声处理、离心过滤可制得提纯凹土粉,使凹凸棒石含量(w)由提纯前的15%提高到55%。2)在提纯后的凹土粉中加入硬脂酸、二甲苯、异丙醇、非离子型表面活性剂(聚氧乙烯油醇醚型),经搅拌、加热、过滤、烘干,可制得改性凹土粉末,其矿物杂质包裹很少,棒状晶较短,交叠少,分散性好。3)从涂料的干燥性和防氧化性考虑,凹土基涂料的较优配比(w)为:改性凹土粉50%、铝矾土10%、氧化锆5%、二氧化硅15%、无定形碳粉5%、片状碳粉5%、硅酸钠5%、分散剂5%。涂覆该涂料的碳钢片在1 000℃保温2 h氧化后的脱碳层厚度只有0.05 mm,说明该涂料能较好地抑制碳钢的高温脱碳氧化。An anti-oxidation coating with a solid content of 50 mass%was prepared using Xuyi attapulgite powder(d 50=3.5μm)as the raw material,purifying,modifying,adding different amounts of bauxite,zirconia,sillica,carbon powder,ammonium polyacrylate,methyl cellulose,etc.and ball milling.The drying test and the oxidation test of carbon steel sheet were carried out.The results show that:(1)the attapulgite powder can be purified by adding a small amount of sodium hexametaphosphate and tween 20 active agent,ball milling,ultrasonic processing and centrifugal filtering;the purified powder has an attapulgite content of 55%compared with the original one of 15%;(2)the modified attapulgite powder can be obtained after adding stearic acid,xylene,isopropanol and nonionic surfactants(polyoxylene oil alcohol ether type)into the purified attapulite powder,stirring,heating,filtering and drying,which has few mineral impurities,short rod crystals,little overlap and good dispersibility;(3)considering the dryness and oxidation resistance of the coating,the optimum formulation of the attapulgite-based coating is as follows:50%modified attapulgite powder,10%bauxite,5%zirconia,15%silica,5%amorphous carbon powder,5%flake carbon powder,5%sodium silicate,and 5%dispersing agent,by mass;the decarburized layer thickness of the coated carbon steel is only 0.05 mm after oxidation at 1 000℃for 2 h,indicating that the coating can better inhibit the high-temperature decarburization and oxidation of carbon steel.

关 键 词：凹土 防氧化涂料 提纯 改性 碳钢 高温防护 干燥性 抗热震性 

分 类 号：TQ630[化学工程—精细化工]