Damage Modeling for Designing High-Performance Roll Materials

摘要

Further advances in the development of roll materials for hot rolling mills require deeper quantitative understanding of roll/strip interactions, combining real-time observations with physical and mathematical modeling of rolling operation, such that damage phenomena are recorded as a function of the thermo-mechanical loads acting on the rolls. Effects of mechanical and thermal loadings on work rolls must be evaluated both at macroscopic and microscopic scales. At macroscopic scale, one must determine how the loads distribute in the component as a whole, considering the overall dimensions and the bulk properties of the rolls. Analysis at the microscopic scale aims to calculate how stresses are distributed over the material microstructure, considering both the macroscopic loads and the characteristics of the micro constituents (matrix, second phase particles and matrix/particle interfaces), such as type, dimensions, distribution and mechanical and physical properties. A collaborative project involving Villares Rolls, Institute for Technological Research and University of Sao Paulo aimed to model the progressive damage of hot rolling roll based on physical and mechanical properties of the micro-constituents of the roll material, thus allowing to design materials with "engineered microstructure" for high performance hot rolling rolls.This work presents results concerning damage modeling and experimental validation through pilot rolling mill, including the comparison between industrial and pilot scale damaged rolls.