The ultrasonic mold was designed for the ceramic powder compression. CAD and CAE were used in the design to analyze the mold strength and its natural frequency. The study of stress distribution and compression in upper and lower punch, mold body and waveguide comparison of stresses was analyzed by FEA experiments under maximum compression at 50,000 N to validate the results of both methods and the mold natural frequency. The difference between FEA and experimental analysis was 3-7%, acceptable. The redesign results in a cylindrical mold body with the outer diameter of 80 mm, the height of 100 mm, and the upper punch of 125 mm in length. The six sides are 26 mm of the high waveguide with 100 mm height. The internal and external diameters are 80 and 110 mm, respectively. The mold has been redesigned and can support the maximum compression force of 1,500 kN. with the bearing steel, AISI 52100, obtainable hardness 65 HRC, the stress concentration occurs at the neck of the upper punch using the ultrasonic at 12.00 to 12.45 kHz.

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The "collector" method of uniaxial dry compacting homogeneously dense powdered bodies of complex shape without macroscopic defects has been developed. It was based on the selfalignment of uniform density regions within a green compact by design of special mold to reduce die-wall friction effects. An equation was proposed that determined the density differential throughout the height of a green compact, which depended on geometrical parameters, and required the controlled movement of die parts. The technique of pressing with the collector method has been developed and patented by TPU. Based on the principles of the collector method a compaction mold of spiral type was modeled for compaction of cylindrical compacts with two alternating, oppositely-moving parts of the passive shaping surface with sliders, twisted at an angle of 36 degrees. The process of powder compaction was simulated by finite element method. The simulation results of the deformation process in the compacts showed that the density of each layer distributed irregularly with the curvature of isosurfaces in the direction of movement of the punch. The results of comparative simulation showed that the statistical dispersion of local values of the deformation of the green compacts made by collector method with the mold of spiral type is reduced to 48% when compared with conventional static compaction and reduced to 5% when compared with collector compaction using the mold of non-spiral type. This method decreases the density gradients. It can be applied to manufacture ceramic articles from nanopowders like impellers and plates with longitudinal holes.

This research is an analysis of stiffener plate dimensions at the column base of the overhanging traffic sign post under effect on vehicle-induced gusts. The finite element analysis (FEA) result is compared with the result form computation using mathematical equation and an experimental result which cited from Fongsamootr T. and Chartpuk P. [2006]. It is found that the FEA result has deviation about 1% and 8% respectively. Traffic sign post structure is exerted by three forces in the same time; body force, Vehicle-Induced Gusts and wind load. The higher stiffener plate leads to decrease of maximum stress at the column base. Height extension of stiffener plate from 250 to 350 mm with fixed thickness and base width leads to increase in the safety factor of column and stiffener plate. Rectangular stiffener plate with cut off a corner (type C) is the best type for supporting the base of traffic sign post column. Cutting of a corner of rectangular stiffener plate results increase of stress in itself but less than maximum stress in traffic sign post column.

This research is a comparison of the characteristics of the displacement isolines