膏剂法渗铝工艺及性能的研究

Investigation on Processes and Property of Paste-Calorizing

研究了膏剂法渗铝中渗剂的配比、渗铝时加热温度和保温时间以及粘结剂的类型对Q235钢表面渗铝层的组织和抗高温氧化性能的影响.结果表明:膏剂法渗铝时,随渗剂配比中铝粉含量的增加,渗铝层深度增加;但当铝粉含量达到35%时,表面粘铝现象较严重.因此铝粉的含量最好是在20%～30%范围内.而且渗铝时加热温度越高,保温时间越长,渗铝层深度越深.粘结剂的酸碱性也对试样表面渗铝层的深度有影响,采用的粘结剂最好为中性的聚乙烯醇.不论是何种渗剂配比,渗铝后其试样的抗氧化能力均比未处理的高.并且渗剂配比中铝粉含量越高,其抗氧化能力就越高.

The effects of aluminizing agent composition, heating temperature and holding time, and adhesion agents on microstructure and oxidation resistance of steel Q235 are investigated. The results show that depth of alumetized layer increases with the increase in aluminum powder content in alumetizing agent. The best result is achived when aluminum content is between 20 to 35 percent. Aluminum will stick on surface when its content reaches 35 percent. The higher heating temperature and the longer holding time result in a increasing depth of the aluminized layer. Neutral material, such as polyvinyl alcohol had better be selected as adhesion agent. Resistance to oxidation of the alumetized specimens is higher than that of untreated one, and the oxidation resistance is improved with the increase in aluminum content in aluminizing agent.