title: [Influence on microstructure of dental zirconia ceramics prepared by two-step sintering].
abstract: OBJECTIVE
  To investigate the microstructure of dental zirconia ceramics prepared by two-step sintering.
  
  
  METHODS
  Nanostructured zirconia powder was dry compacted, cold isostatic pressed, and pre-sintered. The pre-sintered discs were cut processed into samples. Conventional sintering, single-step sintering, and two-step sintering were carried out, and density and grain size of the samples were measured. Afterward, T1 and/or T2 of two-step sintering ranges were measured. Effects on microstructure of different routes, which consisted of two-step sintering and conventional sintering were discussed. The influence of T1 and/or T2 on density and grain size were analyzed as well.
  
  
  RESULTS
  The range of T1 was between 1450 degrees C and 1550 degrees C, and the range of T2 was between 1250 degrees C and 1350 degrees C. Compared with conventional sintering, finer microstructure of higher density and smaller grain could be obtained by two-step sintering. Grain growth was dependent on T1, whereas density was not much related with T1. However, density was dependent on T2, and grain size was minimally influenced.
  
  
  CONCLUSIONS
  Two-step sintering could ensure a sintering body with high density and small grain, which is good for optimizing the microstructure of dental zirconia ceramics.
authors.affiliation: Functional Materials Laboratory, School of Manufacturing Science and Engineering, Sichuan University, Chengdu 610065, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Jian
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.forename: Zhikai
authors.initials: Z
authors.lastname: Wu
authors.forename: Jing
authors.initials: J
authors.lastname: Teng
authors.forename: Jiazhen
authors.initials: J
authors.lastname: Yan
mesh_terms: D002516:Ceramics; D015040:Zirconium
chemical_list: D015040:Zirconium; C028541:zirconium oxide