The Forming Theory and Computer Simulation of the Rotary Cutting Tools with Helical Teeth and Complex Surfaces
This paper researched the forming theory of the cutting tools with helical teeth and complex surfaces. Deduced the nonlinear equations of the movement of NC system to generate such tools, presented the way to find the solution of the equations, calculated the cross section graphics of the teeth profile and computer simulation of NC machining.
A study on a virtual manufacturing model of a revolving milling cutter in 2-axis numerical control processing
Abstract This paper introduces the same and different points of relative problems in virtually manufacturing a revolving milling cutters that are under two different definitions: equal helix lead cutting edge and equal helix angle cutting edge. The relative problems include the design of the cutting edge curves, the design of the groove and the grinding wheel, the design of the feed speed in 2-axis NC processing, the actual groove curved surface, computer simulation, post-processing, etc. It also gives corresponding common mathematical models and some examples. Finally, some useful conclusions are drawn.
Mechanical behaviour and durability of high volume fly ash cementitious composites
The purpose of this research is to separate different morphological particles of ASTM class F fly ash, and study their effect on mechanical behaviour and durability of high volume cementitious mixtures. In this research wet separation of raw fly ash is carried out, which resulted in three layers of different morphological particles. The first layer of particles float, comprise of about 1-5% of fly ash, is identified as cenospheres or hollow spheres. The second layer of particles is measured to be 55-60% of raw fly ash and consisting of porous spherical and rounded particles rich in Si and Al. The third layer particles is measured to be about 35-40% of raw fly ash. High volume fly ash cementitious composites containing second or third layer particles are tested under compression and bending, highlighting a higher strength and ductility in comparison to cementitious ones containing raw fly ash particles. KEYWORDS. Cementitious matrix; Raw fly ash; Second layer particles; Third layer particles.