Research on Ceramic Manufacturing for Creating and Solving Ceramic Formulations Model

This paper describes some theories on basic designing optimization problem, and then establishes the multi-objective optimization mathematical model of ceramic blank. It transforms the ceramic formulation problem in real-world into a mathematical algorithm problem. It also provides a good theoretical basis for a computer to process ceramic formulation. Finally, we transforms the ceramic blank problem from mathematical problem into matrix equation, solving the quality percentage of each ingredient in the formulation program, which has achieved some good results to a certain extent, but still requires further study.

Study of Adaptability of the Compound of Sulfonate Acid Water Reducing Agent with Ceramic Slurry Blank

In this study, we investigate the effect of four types of water reducing agen on fluidity, suspensibility, thixotropy and the particle size of ceramic slurry and analyze the corresponding mechanism. Those water reducing agen include Lignin sulfonate water reducing agent, Sodium metasilicate, naphthalene sulfonate formaldehyde condensate, and the inorganic compound reducing agent. Experiment results shows that the relative molecular mass, the structure of water reducer, the content, and the moisture content of ceramic blank particle can play an important role in the adaptability of both water reducing agen and ceramic slurry. We make a mixed water reducer with lignin sulfonate, sodium metasilicate, and naphthalene sulfonate formaldehyde condensate by the corresponding appropriate mass ratio: 3:2:1. Then we add the mixed water reducing agen by the total dosage of 0.6% into the designed ceramic castable. We find that the performance of the slurry is considerably better improved by the mixed water reducing agen than by either a single one or by the currently commercial inorganic compound reducing agent, such as better improvements in liquidity, the slurry particle size, the mechanical strength of dry body, and the damage strength of porcelain body.

Fracture Resistance and Failure Location of Zirconium and Metallic Implant Abutments

Aim The purpose of this study was to evaluate the fracture resistance and failure location of single-tooth, implant-supported, all-ceramic restorations on different implant abutments subjected to a maximum load. Methods and Materials Forty Certain 3i implants and 20 ITI Straumann implants were used in this study in combination with 20 UCLA abutments, 20 ZiReal abutments, and 20 synOcta Ceramic Blanks to form three groups according to abutment type. All 60 abutments were prepared with standard measurements: a 1.0 mm deep chamfer, 2.0 mm of incisal reduction, and a total height of 7 mm. Sixty IPS Empress 2 full ceramic crowns were fabricated and cemented on each abutment with a resin cement. Static loading was simulated under maximum loading and fracture locations were noted. Results The mean load to failure data and standard deviations for the three groups were as follows: Group 1 (792.7 N ± 122.5) and Group 3 (793.6 ± 162.3) showed no significant difference in fracture resistance while the values for specimens in Group 2 (604 N ± 191.1) had the lowest mean value and were significantly lower. In Group 1, 16 crowns and four abutment fractures were reported, while in Group 3, 17 crowns and three abutments fractured. Group 2 actually showed three types of fractures. Two specimen fractures were located at the implant level, six with fractures occuring within the Empress 2 all-ceramic crown, and the remaining 12 failures were located at the abutment level. Conclusion Within the limitations of this laboratory study, the following conclusions were drawn: The mean load-to-failure values for all three groups were well above the reported normal maximal incisal load range. The load to failure for both the zirconium oxide (ZrO2) abutments (ZiReal on 3i Certain implants and synOcta Ceramic Blanks on SLA ITI Straumann implants) had mean fracture loads of 792.7 N (+122.6) and 604.2 N (+191.2), respectively. The zirconium oxide (ZrO2) ZiReal and titanium (UCLA) abutments on the 3i Certain implants had statistically significantly higher fracture loads (792.7 N and 703.7 N, respectively) than those recorded for the 3i Ceramic Blank abutments on the SLA ITI Straumann implant (604.2 N). The ITI Straumann Ceramic Blank abutments showed uniform fracture behavior. Fracture mainly emanated from the cervical buccal aspect of the abutment. Clinical Significance The three abutments tested showed they can withstand clinical loads above the normal range of mastication. Citation Aramouni P, Zebouni E, Tashkandi E, Dib S, Salameh Z, Almas K. Fracture Resistance and Failure Location of Zirconium and Metallic Implant Abutments. J Contemp Dent Pract 2008 November; (9)7:041-048.

Novel Shrinkage-Free Structural Ceramic Materials for Gas Turbine Applications

The paper presents results of development of the novel shrinkage-free, adaptable to machining and easily welded alumo-boron-carbide silicon materials that experience the cermet stage during their manufacturing. A specific feature of the like ceramics is their double-stage sintering process when, after the original stage, a metal-ceramic blank has a sufficient strength and is easily machined by conventional metal-cutting tools. In addition, such materials are electrically conductive, therefore, the elasto-erosion treatment technique can be applied. Subsequently, a machined part is finally sintered, whereas all the geometries remain actually unchanged due to the shrinkage absence. Prior to the final sintering, all separate parts can be joined by the diffusion welding with the seam strength being 5–10% different from the strength of the main part. The paper provides an insight into the processes and results of tests of the representative selections of samples of four types of the structural ceramics that are experiencing the cermet stage during the process of their formation. Also, ceramic parts for the CGTE hot passage are demonstrated.