Abrasive Water Jet Machining – The Review
Abrasive water jet machining (AWJM) is a relatively new machining technique. Abrasive Water Jet Machining is extensively used in many industrial applications. AWJM is a nonconventional machining process where material is removed by impact erosion of high pressure high velocity of water and entrained high velocity of grit abrasives on a work piece. There are so many process parameter affect quality of machined surface cut by AWJM. Important process parameters which mainly affect the quality of cutting are traverse speed, hydraulic pressure, stand of distance, abrasive flow rate and types of abrasive. Important quality parameters in AWJM are Material Removal Rate (MRR), Surface Roughness (SR), kerf width, tapering of kerf. This paper reviews the research work carried out so far in the area AWJM.
Experimental Optimization of Kerf Taper in EN-8 by Abrasive water Jet Machining Process
: In this paper, the cutting of medium carbon steel (EN-8) with respect to different parameters i.e water jet pressure, abrasive flow rate and traverse speed, were taken for abrasive water jet machining process. Kerf taper of EN-8 steel are measured with respect to the above-mentioned input parameters by using Taguchi L9 array Design of Experiments. From Taguchi methods smaller the better is consider for the optimization in kerf angle
Mathematical Time and Physical Time in the Theory Of Relativity
In the Theory of Relativity time is an imaginary quantity that can not be observed; it is a multiplication of a number that indicates duration of material change and number i that is an imaginary number. i on the square is -1. Time i⁄t is a mathematical time that describes the speed and the duration of material change. In the Universe one can observe physical time only as a stream of material change. It is not that change run in physical time, change itself is physical time.. Distinction between imaginary mathematical time and visible physical time opens some new perspectives into interpretation of Theory of Relativity. c