Research On Quantitative Method Of CARR Reactor Neutron Depth Profile

The Neutron depth profile(NDP)analysis technique is a non-destructive analysis technique that obtains the information on the profile distribution of the near-surface element concentration with high precision.NDP is based on the principle of neutron capture of light elements in the sample to produce heavy charged particles,and the concentration profile distribution of the light elements in the sample is related to the residual energy distribution measured after the heavily charged particles pass through the solid material.This paper uses the neutron depth profile experimental equipment in China Advanced Research Reactor(CARR)of China Institute of Atomic Energy,and Monte Carlo simulation software,inversion iterative method,SRM-2137 and other samples,to do some work on the NDP,(1)The paper studies basic principles and experimental methods of neutron depth profile technology,establishes principle model of neutron depth profile measurement,and proposes the corresponding theoretical calculation method.(2)Monte Carlo software was used to simulate NDP experiment,and constructed the response function matrix and inversion calculation method.The simulation results were verified by experiments,and simulation maximum relative error was not more than 4%.(3)The SRM-2137 standard sample and other experimental samples were measured by NDP measuring equipment in CARR reactor,and the feasibility and accuracy of the inversion calculation method are verified by comparing the simulation results with the physical results.The maximum relative error between the experimental measurement calculation result and the reference data given by the standard sample is 3.4%,and the maximum relative error between the simulation calculation result and the reference data given by the standard sample is no more than 4%.According to the research results,the system and algorithm are improved.Based on CARR reactor NDP equipment,this paper realizes the measurement and analysis of neutron depth profile technology and establishes a complete theoretical analysis method of neutron depth profile.By reference material SRM-2137 to verify the feasibility and accuracy of this method of analysis,the 20% maximum relative error between the initial calculation result and the actual distribution is improved to 4%,which greatly improves the accuracy of the calculation.