Method for determining boron content in steel

The invention belongs to the technical field of boron content determination and in particular relates to a method for determining boron content in steel. The method comprises the following specific steps: weighing samples, adding a phosphoric acid solution and a sulfuric acid solution, heating until the samples are totally dissolved, slowly adding hydrogen peroxide, fuming at a low temperature, cooling, and adding a water-soluble salt for fixing the volume; adding a fixed-volume sample solution into a hydrofluoric acid solution, shaking up, completing complexation, adding water, a methylene blue solution and dichloroethane; fully shaking, standing and extracting; placing the lower solution in a cuvette, and determining the absorbance by a spectrophotometer; selecting standard samples of different gradient boron content, treating the samples according to the previous method, taking the boron percentage content as a horizontal ordinate, taking the absorbance as a vertical coordinate, anddrawing a standard curve