Improving adhesion between luting cement and zirconia-based ceramic with an alternative surface treatment

This study evaluated the influence of an alternative surface treatment on the microshear bond strength (μsbs) of zirconia-based ceramic. Thirty-five zirconia disks were assigned to five groups according to the following treatments: Control (CO), glass and silane were not applied to the zirconia surface; G1, air blasted with 100μm glass beads + glaze + silane; G2, a gel containing 15% (by weight) glass beads applied to the ceramic surface + glaze + silane; G3, a gel containing 25% (by weight) glass beads applied to the ceramic surface + glaze + silane; and G4, a gel containing 50% (by weight) glass beads applied to the ceramic surface + glaze + silane. The specimens were built up using RelyX ARC®, according to the manufacturer’s recommendations, and inserted in an elastomeric mold with an inner diameter of 0.8 mm. The μsbs test was performed using a testing machine at a crosshead speed of 0.5 mm/min. ANOVA and Tukey’s test (p < 0.05) were applied to the bond strength values (in MPa). CO (15.6 ± 4.1) showed the lowest μsbs value. There were no statistical differences between the G1 (24.9 ± 7.4), G2 (24.9 ± 2.3), G3 (35.0 ± 10.3) and G4 (35.3 ± 6.0) experimental groups. Those groups submitted to surface treatments with higher concentrations of glass showed a lower frequency of adhesive failures. In conclusion, the glass application improved the interaction between the ceramic and the luting cement

The Pharmacogenomics Research Network Translational Pharmacogenetics Program: Outcomes and Metrics of Pharmacogenetic Implementations Across Diverse Healthcare Systems

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138257/1/cpt630-sup-0001-suppinfo1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138257/2/cpt630_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138257/3/cpt630.pd

Influence of process parameters on the microstructure and casting defects of a LPDC engine block

The growing demand in the automotive industry for lighter vehicles has led to increasing use of Al-Si based alloys in the production of engine blocks. Low-pressure die casting (LPDC) is an enhanced process generally used for parts with premium requirements, therefore it is one of the most promising technologies for the production of engine blocks. This work is aimed to study the effects of Sr modification and holding pressure on the microstructure and casting defects of a low-pressure die cast A356 engine block. The microstructural scale, evaluated by secondary dendrite arm spacing, the amount of porosity and inclusions, and the morphology of eutectic Si particles were investigated by metallographic and image analysis. The results were correlated with the variation of input process variables such as holding pressure and Sr level. The measured amount of porosity is low, therefore confirming LPDC as a useful foundry process for the production of Al blocks for high performance engines