Research On The Measuring Method Of The Size And Shape Of Particles Used In Precision Casting Based On Digit Photomicrography And Particle Image Recognition

The thesis introduced the computer micrograph gathering system using a digital camera and particle measurement techniques based on Digital Image Process technology in detail. Develop a measuring system to obtain particle's(include covering material for casting) characteristices such as shape , area , perimeter ,particle distribution .etc. This system adopt object-oriented develop method and regard various index of particle as the basic data structure, under the enviroment of VC++6. O.The system has characteristices of high- efficient, accurate and easy to use because it realizes the functions of automatic revise, automatic cutting apart, automatic edge following, automatic measuring, automatic storing of particle etc, can have been heavy to raise the speed and accuracy of particle measurement, reduce the artificial error. Adopted such techniques as image detecting, zone optioning.image absolute units calibration, selective erasing, image statistic analysis .etc, make the measuring result more close to real value..Used average method to eliminate the stochastic noise. Choiced dispersant agent to reduce Brownnian movement. Professional hotograph technique make the image more idealization, ensure the measure resultmore accuracy.The thesis described the over design of the software system, detailed introduced the design method and function of each module. Supplied some effect graph, and processed the measured data to physical circumstance.Proved the method was feasible.Normal screen seperattion method can not detect particle size of 70um above, to detect the particle size which in 5~70um is very important and necessary. Used large quantity of experiments to proved the feasibility and validity to measure particle size of the range.