Solution Treatment of 20LH5 Chromium-Manganese Austenitic Stainless Steel

Abstract

In this study, based on the existing 20LH5 austenitic stainless steel for sieve, the influence of different solution treatment parameters on the microstructure and properties were studied. Through the simulation before the experiment, the suitable theoretical solution treatment temperature range for the steel plate is 800 °C~1100 °C according to the empirical formula, and the optimal holding time range is 5 s-15 s. In the optimal temperature range and the best solution treatment time, the gradient was set in the interval and then cooled by water and air after heating. The results show that the grain of the sample steel before pre-treatment (cold rolled then pre-annealed before leaving the factory) is coarser, and the microstructure of the steel plate after solution treatment has obvious refinement tendency and a large number of annealing twins are formed. The softening effect is remarkable. At 800 °C + 15 s + water cooling and 950 °C + 10 s + water cooling, the tensile strength of the two processes are greater than 1000 MPa, the yield strength of the two processes are greater than 440 MPa, and the elongation of the two processes are greater than 46%.The steel sheets obtained by solution treatment under both experimental parameters can achieve good mechanical properties and meet the expected specifications of the products.