氧化铁粉末化学组成对合成SHS复合弯管内衬陶瓷的影响

基于重力分离SHS法制备陶瓷内衬复合弯管 ,研究了氧化铁粉末化学组成对SHS复合弯管内衬陶瓷的影响 .研究发现在铝热剂相同质量分数条件下 ,存在于工业原料Fe2 O3 粉末的杂质比SiO2 添加剂对燃烧过程的稀释效应更为强烈 .在工业原料Fe2 O3 +Al体系中加入适量的Fe3 O4+Al体系 ,使燃烧温度、蔓延速率及SHS反应转化率均有所升高 ;但加入过量的Fe3 O4+Al体系 ,虽然使蔓延速率进一步增大 ,但却引起燃烧温度和SHS反应转化率有所下降 .实验表明 ,在工业原料Fe2 O3 +Al体系中加入 1 5 %的Fe3 O4+Al体系 ,使复合弯管内衬陶瓷性能达到并超过用分析纯Fe2 O3+Al体系所制备的复合弯管内衬陶瓷性能 .

Influences of iron oxide powder chemical composition on synthesizing lined ceramics of SHS curved composite pipes

On basis of using gravitational separation SHS method to produce curved ceramic-lined composite pipes, influences of Fe 2O 3 powder chamical composition on lined ceramics of SHS curved composite pipes have been investigated. It was found that the dilution effect of impurity in Fe 2O 3 raw powder was increased compared with one of SiO 2 additive under same mass fraction in thermit. Adding Fe 3O 4+Al system with suitable addition in raw Fe 2O 3+Al system could cause combustion temperature, propagating rate and SHS transformation rate to be increased, whereas addition of Fe 3O 4+Al system in Fe 2O 3+Al system was beyond certain value, combustion temperature and SHS transformation rate could be reduced though propagating rate was increased further. It was demonstrated from the experiment that as adding Fe 3O 4+Al system with 15% addition in raw Fe 2O 3+Al system, properties of lined ceramics of curved composition pipes could reach or exceed ones of that produced with chemically pure Fe 2O 3+Al system.