Study On Deformation Behavior And Grain Refinement Of 08F Steel In Process Of Stepping Continuous Extrusion-rolling

Low carbon steel has low price and high yield, it becomes widely used material in industrial production, so improve the comprehensive properties of low carbon steel further is very important. There is great relationship between material properties and grain size, so plastic deformation becomes an important way to bring out grain refinement, to improve the properties. But traditional large plastic deformation is limited by the way of deformation, it is unable accumulate amount of deformation through the unlimited deformation. The severe plastic deformation can break through this limit. make the metal material get very large deformation to bring out grain refinement at low temperature, but so far. severe plastic deformation method cannot realize the industrialized production of large size metal materials. This article, we use the method of continuous extrusion-rolling, studying grain refinement of metal materials and large deformation technology for continuous production.This article we develop orthogonal experimental program. Through finite element simulation the specimen in the process of extrusion-rolling deformation at first. finding conditions for deformation can be well. And then select the 08F steel plate with a thickness of2mm as raw material, respectively, through 1 time,2 times,3 times and 4 times extrusion-rolling deformation experiments on the samples, then through different annealing temperature (300℃,330℃,360℃,390℃) and annealing time (lOmin,15min, 20min,30min) heat treatment process on the sample, observing the microstructure after extrusion deformation and heat treatment of steel, grain size decrease with number of rolling deformation and larger with the increase of temperature and time. The research shows that, Optimum conditions for extrusion-rolling deformation experiment of08F steel are:deforming 3 passes, annealing temperature is 360 ° C, annealing time is 15 min,the morphology and grain size of the best, the grain size is 5.97μm.