乳胶+PVA体系水基流延成型99氧化铝陶瓷材料

Aqueous Tape Casting of the 99 Alumina Substrate Using PVA+B-1070 Cobinder

研究了乳胶+PVA复合粘结剂体系水基流延浆料制备99氧化铝陶瓷基片。通过研究浆料pH值、分散剂、粘结剂的比例等因素对水基流延浆料流变学性能的影响,得到了水基流延浆料的最佳配比范围。当pH值为9.0时,分散剂PAA含量为粉料的0.8%(质量分数)时能获得固含量为55vol%、稳定分散的氧化铝浆料。研究表明PVA与乳胶的化学相容性好,采用两种粘结剂复合,可以互补不足。加入复合粘结剂4.5%(质量分数)(乳胶:PVA=7:3),制备出的99氧化铝素坯片其厚度可在50～1000μm之间进行调控,素坯相对密度可以达到56%左右。制备的流延片在烧结温度1650℃、保温2h的条件下获得了相对密度为98.5%、平整、半透明的99氧化铝陶瓷基片。

In the paper, a cobinder, consisting of polyvinyl alcohol （PVA） and PAA latex, was used to prepare the 99 alumina substrate via aqueous tape casting. The rheological properties of alumina slurry as the function of the pH value, the amount of dispersant and binder were discussed. The high volume of solid-loading slurry with stability, appropriate viscosity and easy-casting could be obtained. The stable slurry with solid loading of 55vo1% was produced at the pH value of 9.0 and dispersant PAA content of 0.8 wt%. The research shows that the chemical compatibility was good between PVA and latex. The better effect can be accessed using co-binder of PVA and latex. The green tape with 56% relative density and the thickness of 50-1000 μm can be obtained via adding 4.5 wt% co-binder （latex：PVA = 7：3）. The fiat and translucent alumina substrate with above 98.5% relative density could be produced at the sintering temperature of 1650 ℃ for 2 h.